Detach materialized SQL rows from transaction lifetime

bin/deploy_all

@@ -20,7 +20,7 @@
 set -e
 echo "publishing all artifacts"
 echo
-./gradlew publishToMavenLocal site:jsBrowserDistribution publish buildInstallablePlugin :lyng:linkReleaseExecutableLinuxX64 :lyng:installJvmDist --parallel #--no-configuration-cache
+./gradlew publishToMavenLocal site:jsBrowserDistribution publish buildInstallablePlugin :lyng:linkReleaseExecutableLinuxX64 :lyng:installJvmDist --parallel --no-configuration-cache
 
 #echo
 #echo "Creating plugin"

docs/lyng.io.db.md

@@ -205,7 +205,8 @@ assertThrows(RollbackException) {
 - `columns` — positional `SqlColumn` metadata, available before iteration.
 - `size()` — result row count.
 - `isEmpty()` — fast emptiness check where possible.
-- `iterator()` / `toList()` — normal row iteration.
+- `iterator()` — normal row iteration while the transaction is active.
+- `toList()` — materialize detached `SqlRow` snapshots that may be used after the transaction ends.
 
 ##### `SqlRow`
 
@@ -370,14 +371,24 @@ PostgreSQL-specific notes:
 
 #### Lifetime rules
 
-Result sets and rows are valid only while their owning transaction is active.
+`ResultSet` is valid only while its owning transaction is active.
+
+`SqlRow` values are detached snapshots once materialized, so this pattern is valid:
+
+```lyng
+val rows = db.transaction { tx ->
+    tx.select("select name from person order by id").toList()
+}
+
+assertEquals("Ada", rows[0]["name"])
+```
 
 This means:
 
-- do not keep `ResultSet` or `SqlRow` objects after the transaction block returns
-- copy the values you need into ordinary Lyng objects inside the transaction
+- do not keep `ResultSet` objects after the transaction block returns
+- materialize rows with `toList()` inside the transaction when they must outlive it
 
-The same lifetime rule applies to generated keys returned by `ExecutionResult.getGeneratedKeys()`.
+The same rule applies to generated keys from `ExecutionResult.getGeneratedKeys()`: the `ResultSet` is transaction-scoped, but rows returned by `toList()` are detached.
 
 ---
 

examples/sqlite_basic.lyng

@@ -65,7 +65,7 @@ db.transaction { tx ->
         println("  #" + row["ID"] + " " + row["title"] + " done=" + row["done"] + " due=" + row["due_date"])
     }
 
-    // If values need to survive after the transaction closes, copy them now.
+    // toList() materializes detached rows that stay usable after transaction close.
     val snapshot = tx.select("select title, due_date from task order by id").toList()
     assertEquals("Write a SQLite example", snapshot[0]["title"])
     assertEquals(Date(2026, 4, 16), snapshot[1]["due_date"])

lyng/build.gradle.kts

@@ -151,8 +151,13 @@ kotlin {
 
 tasks.named<KotlinNativeTest>("linuxX64Test") {
     dependsOn(tasks.named("linkDebugExecutableLinuxX64"))
+    dependsOn(tasks.named("linkReleaseExecutableLinuxX64"))
     environment(
         "LYNG_CLI_NATIVE_BIN",
         layout.buildDirectory.file("bin/linuxX64/debugExecutable/lyng.kexe").get().asFile.absolutePath
     )
+    environment(
+        "LYNG_CLI_NATIVE_RELEASE_BIN",
+        layout.buildDirectory.file("bin/linuxX64/releaseExecutable/lyng.kexe").get().asFile.absolutePath
+    )
 }

lyng/src/commonMain/kotlin/Common.kt

@@ -119,8 +119,9 @@ internal class CliExecutionRuntime(
                 facade.call(handler)
             }
         }
-        session.cancelAndJoin()
+        session.cancel()
         shutdownSystemNetEngine()
+        session.join()
     }
 
     fun shutdownBlocking() {

lyng/src/linuxTest/kotlin/net/sergeych/lyng_cli/CliWebSocketNativeRegressionTest.kt

@@ -0,0 +1,132 @@
+/*
+ * Copyright 2026 Sergey S. Chernov real.sergeych@gmail.com
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package net.sergeych.lyng_cli
+
+import kotlinx.cinterop.*
+import okio.FileSystem
+import okio.Path
+import okio.Path.Companion.toPath
+import platform.posix.O_CREAT
+import platform.posix.O_TRUNC
+import platform.posix.O_WRONLY
+import platform.posix.SIGKILL
+import platform.posix.SIGSEGV
+import platform.posix._exit
+import platform.posix.close
+import platform.posix.dup2
+import platform.posix.execvp
+import platform.posix.fork
+import platform.posix.getenv
+import platform.posix.getpid
+import platform.posix.kill
+import platform.posix.open
+import platform.posix.usleep
+import platform.posix.waitpid
+import kotlin.test.Test
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+@OptIn(ExperimentalForeignApi::class)
+class CliWebSocketNativeRegressionTest {
+    @Test
+    fun releaseCliDoesNotSegfaultOnConcurrentWebSocketClients() {
+        val executable = getenv("LYNG_CLI_NATIVE_RELEASE_BIN")?.toKString()
+            ?: error("LYNG_CLI_NATIVE_RELEASE_BIN is not set")
+        val fs = FileSystem.SYSTEM
+        val repoRoot = ascend(executable.toPath(), 6)
+        val scriptPath = repoRoot / "bugs" / "ws-segfault.lyng"
+        check(fs.exists(scriptPath)) { "bug repro script not found at $scriptPath" }
+
+        val tempDir = "/tmp/lyng_ws_native_${getpid()}_${kotlin.random.Random.nextInt()}".toPath()
+        val stdoutPath = tempDir / "stdout.txt"
+        val stderrPath = tempDir / "stderr.txt"
+
+        fs.createDirectories(tempDir)
+        try {
+            val pid = launchCli(executable, scriptPath, stdoutPath, stderrPath)
+            usleep(5_000_000u)
+
+            if (kill(pid, 0) == 0) {
+                kill(pid, SIGKILL)
+            }
+
+            val status = waitForPid(pid)
+            val termSignal = status and 0x7f
+            val stdout = readUtf8IfExists(fs, stdoutPath)
+            val stderr = readUtf8IfExists(fs, stderrPath)
+            val allOutput = "$stdout\n$stderr"
+
+            assertFalse(termSignal == SIGSEGV, "native CLI crashed with SIGSEGV. Output:\n$allOutput")
+            assertTrue(
+                stdout.lineSequence().count { it == "test send to ws://127.0.0.1:9998... OK" } == 2,
+                "expected both websocket clients to finish. Output:\n$allOutput"
+            )
+            assertFalse(allOutput.contains("Segmentation fault"), "process output reported a segmentation fault:\n$allOutput")
+        } finally {
+            fs.deleteRecursively(tempDir, mustExist = false)
+        }
+    }
+
+    private fun ascend(path: Path, levels: Int): Path {
+        var current = path
+        repeat(levels) {
+            current = current.parent ?: error("cannot ascend $levels levels from $path")
+        }
+        return current
+    }
+
+    private fun readUtf8IfExists(fs: FileSystem, path: Path): String {
+        return if (fs.exists(path)) fs.read(path) { readUtf8() } else ""
+    }
+
+    private fun waitForPid(pid: Int): Int = memScoped {
+        val status = alloc<IntVar>()
+        val waited = waitpid(pid, status.ptr, 0)
+        check(waited == pid) { "waitpid failed for $pid" }
+        status.value
+    }
+
+    private fun launchCli(
+        executable: String,
+        scriptPath: Path,
+        stdoutPath: Path,
+        stderrPath: Path,
+    ): Int = memScoped {
+        val pid = fork()
+        check(pid >= 0) { "fork failed" }
+        if (pid == 0) {
+            val stdoutFd = open(stdoutPath.toString(), O_WRONLY or O_CREAT or O_TRUNC, 0x1A4)
+            val stderrFd = open(stderrPath.toString(), O_WRONLY or O_CREAT or O_TRUNC, 0x1A4)
+            if (stdoutFd < 0 || stderrFd < 0) {
+                _exit(2)
+            }
+            dup2(stdoutFd, 1)
+            dup2(stderrFd, 2)
+            close(stdoutFd)
+            close(stderrFd)
+
+            val argv = allocArray<CPointerVar<ByteVar>>(3)
+            argv[0] = executable.cstr.ptr
+            argv[1] = scriptPath.toString().cstr.ptr
+            argv[2] = null
+            execvp(executable, argv)
+            _exit(127)
+        }
+        pid
+    }
+}

lyngio/src/commonMain/kotlin/net/sergeych/lyng/io/db/SqlRuntimeSupport.kt

@@ -21,7 +21,6 @@ import net.sergeych.lyng.Arguments
 import net.sergeych.lyng.ModuleScope
 import net.sergeych.lyng.Scope
 import net.sergeych.lyng.ScopeFacade
-import net.sergeych.lyng.asFacade
 import net.sergeych.lyng.obj.Obj
 import net.sergeych.lyng.obj.ObjBool
 import net.sergeych.lyng.obj.ObjClass
@@ -234,12 +233,10 @@ internal class SqlRuntimeTypes private constructor(
 
         rowClass.addProperty("size", getter = {
             val self = thisAs<SqlRowObj>()
-            self.lifetime.ensureActive(this)
             ObjInt.of(self.values.size.toLong())
         })
         rowClass.addProperty("values", getter = {
             val self = thisAs<SqlRowObj>()
-            self.lifetime.ensureActive(this)
             ObjImmutableList(self.values)
         })
 
@@ -302,14 +299,13 @@ internal class SqlResultSetObj(
     data: SqlResultSetData,
 ) : Obj() {
     val columns: List<Obj> = data.columns.map { SqlColumnObj(types, it) }
-    val rows: List<Obj> = buildRows(types, lifetime, data)
+    val rows: List<Obj> = buildRows(types, data)
 
     override val objClass: ObjClass
         get() = types.resultSetClass
 
     private fun buildRows(
         types: SqlRuntimeTypes,
-        lifetime: SqlTransactionLifetime,
         data: SqlResultSetData,
     ): List<Obj> {
         val indexByName = linkedMapOf<String, MutableList<Int>>()
@@ -317,14 +313,13 @@ internal class SqlResultSetObj(
             indexByName.getOrPut(column.name.lowercase()) { mutableListOf() }.add(index)
         }
         return data.rows.map { rowValues ->
-            SqlRowObj(types, lifetime, rowValues, indexByName)
+            SqlRowObj(types, rowValues, indexByName)
         }
     }
 }
 
 internal class SqlRowObj(
     val types: SqlRuntimeTypes,
-    val lifetime: SqlTransactionLifetime,
     val values: List<Obj>,
     private val indexByName: Map<String, List<Int>>,
 ) : Obj() {
@@ -332,7 +327,6 @@ internal class SqlRowObj(
         get() = types.rowClass
 
     override suspend fun getAt(scope: Scope, index: Obj): Obj {
-        lifetime.ensureActive(scope.asFacade())
         return when (index) {
             is ObjInt -> {
                 val idx = index.value.toInt()

lyngio/src/commonMain/kotlin/net/sergeych/lyngio/ws/KtorWsEngine.kt

@@ -17,35 +17,46 @@ import kotlinx.coroutines.channels.ClosedReceiveChannelException
 
 internal fun createKtorWsEngine(
     engineFactory: HttpClientEngineFactory<HttpClientEngineConfig>,
-): LyngWsEngine = KtorLyngWsEngine(engineFactory)
+    shareClient: Boolean = true,
+): LyngWsEngine = KtorLyngWsEngine(engineFactory, shareClient)
 
 private class KtorLyngWsEngine(
     engineFactory: HttpClientEngineFactory<HttpClientEngineConfig>,
+    private val shareClient: Boolean,
 ) : LyngWsEngine {
-    private val clientResult = runCatching {
+    private val clientFactory: () -> HttpClient = {
         HttpClient(engineFactory) {
             install(WebSockets)
         }
     }
+    private val sharedClientResult = if (shareClient) runCatching { clientFactory() } else null
+    private val supportProbe = if (!shareClient) runCatching { clientFactory().close() } else null
 
     override val isSupported: Boolean
-        get() = clientResult.isSuccess
+        get() = sharedClientResult?.isSuccess ?: supportProbe?.isSuccess ?: true
 
     override suspend fun connect(url: String, headers: Map<String, String>): LyngWsSession {
-        val client = clientResult.getOrElse {
+        val client = (sharedClientResult?.getOrElse {
             throw UnsupportedOperationException(it.message ?: "WebSocket client is not supported")
-        }
+        } ?: runCatching { clientFactory() }.getOrElse {
+            throw UnsupportedOperationException(it.message ?: "WebSocket client is not supported")
+        })
         val session = client.webSocketSession {
             url(url)
             headers.forEach { (name, value) -> header(name, value) }
         }
-        return KtorLyngWsSession(url, session)
+        return KtorLyngWsSession(
+            targetUrl = url,
+            session = session,
+            ownedClient = client.takeUnless { shareClient },
+        )
     }
 }
 
 private class KtorLyngWsSession(
     private val targetUrl: String,
     private val session: DefaultWebSocketSession,
+    private val ownedClient: HttpClient? = null,
 ) : LyngWsSession {
     private var closed = false
 
@@ -55,12 +66,22 @@ private class KtorLyngWsSession(
 
     override suspend fun sendText(text: String) {
         ensureOpen()
-        session.send(text)
+        try {
+            session.send(text)
+        } catch (e: Throwable) {
+            release()
+            throw e
+        }
     }
 
     override suspend fun sendBytes(data: ByteArray) {
         ensureOpen()
-        session.send(data)
+        try {
+            session.send(data)
+        } catch (e: Throwable) {
+            release()
+            throw e
+        }
     }
 
     override suspend fun receive(): LyngWsMessage? {
@@ -68,14 +89,17 @@ private class KtorLyngWsSession(
         val frame = try {
             session.incoming.receive()
         } catch (_: ClosedReceiveChannelException) {
-            closed = true
+            release()
             return null
+        } catch (e: Throwable) {
+            release()
+            throw e
         }
         return when (frame) {
             is Frame.Text -> LyngWsMessage(isText = true, text = frame.readText())
             is Frame.Binary -> LyngWsMessage(isText = false, data = frame.data.copyOf())
             is Frame.Close -> {
-                closed = true
+                release()
                 null
             }
             else -> receive()
@@ -84,11 +108,20 @@ private class KtorLyngWsSession(
 
     override suspend fun close(code: Int, reason: String) {
         if (closed) return
-        closed = true
-        session.close(CloseReason(code.toShort(), reason))
+        try {
+            session.close(CloseReason(code.toShort(), reason))
+        } finally {
+            release()
+        }
     }
 
     private fun ensureOpen() {
         if (closed) throw IllegalStateException("websocket session is closed")
     }
+
+    private fun release() {
+        if (closed) return
+        closed = true
+        ownedClient?.close()
+    }
 }

lyngio/src/commonMain/kotlin/net/sergeych/lyngio/ws/SocketWsEngine.kt

@@ -0,0 +1,392 @@
+package net.sergeych.lyngio.ws
+
+import io.ktor.http.Url
+import io.ktor.http.URLProtocol
+import net.sergeych.lyngio.net.LyngNetEngine
+import net.sergeych.lyngio.net.LyngTcpSocket
+import net.sergeych.lyngio.net.getSystemNetEngine
+import net.sergeych.mp_tools.encodeToBase64
+import kotlin.random.Random
+
+internal fun createSocketWsEngine(
+    secureFallback: LyngWsEngine = UnsupportedLyngWsEngine,
+): LyngWsEngine = SocketLyngWsEngine(getSystemNetEngine(), secureFallback)
+
+private class SocketLyngWsEngine(
+    private val netEngine: LyngNetEngine,
+    private val secureFallback: LyngWsEngine,
+) : LyngWsEngine {
+    override val isSupported: Boolean
+        get() = (netEngine.isSupported && netEngine.isTcpAvailable) || secureFallback.isSupported
+
+    override suspend fun connect(url: String, headers: Map<String, String>): LyngWsSession {
+        val parsedUrl = Url(url)
+        return when (parsedUrl.protocol.name.lowercase()) {
+            URLProtocol.WS.name.lowercase() -> connectPlain(parsedUrl, headers)
+            URLProtocol.WSS.name.lowercase() -> secureFallback.connect(url, headers)
+            else -> throw UnsupportedOperationException("Unsupported websocket scheme: ${parsedUrl.protocol.name}")
+        }
+    }
+
+    private suspend fun connectPlain(url: Url, headers: Map<String, String>): LyngWsSession {
+        if (!netEngine.isSupported || !netEngine.isTcpAvailable) {
+            throw UnsupportedOperationException("WebSocket client is not supported on this runtime")
+        }
+        val socket = netEngine.tcpConnect(url.host, url.port, timeoutMillis = null, noDelay = true)
+        try {
+            val key = randomBytes(16).encodeToBase64()
+            val requestPath = buildRequestPath(url)
+            val hostHeader = buildHostHeader(url)
+            val request = buildString {
+                append("GET ").append(requestPath).append(" HTTP/1.1\r\n")
+                append("Host: ").append(hostHeader).append("\r\n")
+                append("Upgrade: websocket\r\n")
+                append("Connection: Upgrade\r\n")
+                append("Sec-WebSocket-Key: ").append(key).append("\r\n")
+                append("Sec-WebSocket-Version: 13\r\n")
+                headers.forEach { (name, value) ->
+                    append(name).append(": ").append(value).append("\r\n")
+                }
+                append("\r\n")
+            }
+            socket.writeUtf8(request)
+            socket.flush()
+            validateHandshake(socket, key)
+            return SocketLyngWsSession(url.toString(), socket)
+        } catch (e: Throwable) {
+            socket.close()
+            throw e
+        }
+    }
+}
+
+private class SocketLyngWsSession(
+    private val targetUrl: String,
+    private val socket: LyngTcpSocket,
+) : LyngWsSession {
+    private var closed = false
+    private var closeSent = false
+    private var pending = ByteArray(0)
+    private var fragmentedOpcode: Int? = null
+    private var fragmentedPayload = ByteArray(0)
+
+    override fun isOpen(): Boolean = !closed && socket.isOpen()
+
+    override fun url(): String = targetUrl
+
+    override suspend fun sendText(text: String) {
+        ensureOpen()
+        sendFrame(OPCODE_TEXT, text.encodeToByteArray())
+    }
+
+    override suspend fun sendBytes(data: ByteArray) {
+        ensureOpen()
+        sendFrame(OPCODE_BINARY, data)
+    }
+
+    override suspend fun receive(): LyngWsMessage? {
+        if (closed) return null
+        while (true) {
+            val frame = readFrame() ?: run {
+                release()
+                return null
+            }
+            when (frame.opcode) {
+                OPCODE_CONTINUATION -> {
+                    val opcode = fragmentedOpcode ?: throw IllegalStateException("unexpected websocket continuation frame")
+                    fragmentedPayload += frame.payload
+                    if (frame.fin) {
+                        val payload = fragmentedPayload
+                        fragmentedOpcode = null
+                        fragmentedPayload = ByteArray(0)
+                        return payload.toMessage(opcode)
+                    }
+                }
+                OPCODE_TEXT, OPCODE_BINARY -> {
+                    if (frame.fin) return frame.payload.toMessage(frame.opcode)
+                    fragmentedOpcode = frame.opcode
+                    fragmentedPayload = frame.payload
+                }
+                OPCODE_CLOSE -> {
+                    if (!closeSent) {
+                        sendFrame(OPCODE_CLOSE, frame.payload)
+                        closeSent = true
+                    }
+                    release()
+                    return null
+                }
+                OPCODE_PING -> sendFrame(OPCODE_PONG, frame.payload)
+                OPCODE_PONG -> Unit
+                else -> Unit
+            }
+        }
+    }
+
+    override suspend fun close(code: Int, reason: String) {
+        if (closed) return
+        val reasonBytes = reason.encodeToByteArray()
+        val payload = ByteArray(reasonBytes.size + 2)
+        payload[0] = (code shr 8).toByte()
+        payload[1] = code.toByte()
+        reasonBytes.copyInto(payload, destinationOffset = 2)
+        try {
+            if (!closeSent) {
+                sendFrame(OPCODE_CLOSE, payload)
+                closeSent = true
+            }
+        } finally {
+            release()
+        }
+    }
+
+    private suspend fun sendFrame(opcode: Int, payload: ByteArray) {
+        ensureOpen()
+        val header = buildFrameHeader(opcode, payload.size, masked = true)
+        val mask = randomBytes(4)
+        val maskedPayload = payload.copyOf()
+        maskedPayload.indices.forEach { index ->
+            maskedPayload[index] = (maskedPayload[index].toInt() xor mask[index % mask.size].toInt()).toByte()
+        }
+        socket.write(header + mask + maskedPayload)
+        socket.flush()
+    }
+
+    private suspend fun readFrame(): WsFrame? {
+        val head = readExact(2) ?: return null
+        val fin = (head[0].toInt() and 0x80) != 0
+        val opcode = head[0].toInt() and 0x0f
+        val masked = (head[1].toInt() and 0x80) != 0
+        val payloadLength = when (val lengthCode = head[1].toInt() and 0x7f) {
+            126 -> {
+                val extended = readExact(2) ?: return null
+                ((extended[0].toInt() and 0xff) shl 8) or (extended[1].toInt() and 0xff)
+            }
+            127 -> {
+                val extended = readExact(8) ?: return null
+                var acc = 0L
+                extended.forEach { byte ->
+                    acc = (acc shl 8) or (byte.toInt() and 0xff).toLong()
+                }
+                require(acc <= Int.MAX_VALUE.toLong()) { "websocket frame is too large" }
+                acc.toInt()
+            }
+            else -> lengthCode
+        }
+        val mask = if (masked) readExact(4) ?: return null else null
+        val payload = if (payloadLength > 0) readExact(payloadLength) ?: return null else ByteArray(0)
+        if (mask != null) {
+            payload.indices.forEach { index ->
+                payload[index] = (payload[index].toInt() xor mask[index % mask.size].toInt()).toByte()
+            }
+        }
+        return WsFrame(fin = fin, opcode = opcode, payload = payload)
+    }
+
+    private suspend fun readExact(byteCount: Int): ByteArray? {
+        while (pending.size < byteCount) {
+            val chunk = socket.read(maxOf(4096, byteCount - pending.size)) ?: break
+            if (chunk.isEmpty()) break
+            pending += chunk
+        }
+        if (pending.size < byteCount) return null
+        val result = pending.copyOfRange(0, byteCount)
+        pending = pending.copyOfRange(byteCount, pending.size)
+        return result
+    }
+
+    private fun release() {
+        if (closed) return
+        closed = true
+        socket.close()
+    }
+
+    private fun ensureOpen() {
+        if (closed || !socket.isOpen()) throw IllegalStateException("websocket session is closed")
+    }
+}
+
+private data class WsFrame(
+    val fin: Boolean,
+    val opcode: Int,
+    val payload: ByteArray,
+)
+
+private suspend fun validateHandshake(socket: LyngTcpSocket, key: String) {
+    val statusLine = socket.readLine() ?: error("websocket handshake failed: missing response status")
+    require(statusLine.startsWith("HTTP/1.1 101") || statusLine.startsWith("HTTP/1.0 101")) {
+        "websocket handshake failed: $statusLine"
+    }
+    val headers = linkedMapOf<String, String>()
+    while (true) {
+        val line = socket.readLine() ?: error("websocket handshake failed: unexpected EOF")
+        if (line.isBlank()) break
+        val colonAt = line.indexOf(':')
+        require(colonAt > 0) { "invalid websocket header: $line" }
+        val name = line.substring(0, colonAt).trim().lowercase()
+        val value = line.substring(colonAt + 1).trim()
+        headers[name] = value
+    }
+    require(headers["upgrade"]?.lowercase() == "websocket") { "websocket handshake failed: missing Upgrade header" }
+    require(headers["connection"]?.lowercase()?.contains("upgrade") == true) {
+        "websocket handshake failed: missing Connection header"
+    }
+    require(headers["sec-websocket-accept"] == websocketAcceptKey(key)) {
+        "websocket handshake failed: invalid Sec-WebSocket-Accept"
+    }
+}
+
+private fun websocketAcceptKey(key: String): String =
+    sha1((key + WS_GUID).encodeToByteArray()).encodeToBase64()
+
+private fun buildRequestPath(url: Url): String {
+    val path = url.encodedPath.ifEmpty { "/" }
+    val query = url.encodedQuery
+    return if (query.isBlank()) path else "$path?$query"
+}
+
+private fun buildHostHeader(url: Url): String {
+    val host = if (':' in url.host && !url.host.startsWith("[")) "[${url.host}]" else url.host
+    return if (url.port == url.protocol.defaultPort) host else "$host:${url.port}"
+}
+
+private fun buildFrameHeader(opcode: Int, payloadSize: Int, masked: Boolean): ByteArray {
+    require(payloadSize >= 0) { "payload size must be non-negative" }
+    val firstByte = (0x80 or (opcode and 0x0f)).toByte()
+    val maskBit = if (masked) 0x80 else 0
+    return when {
+        payloadSize <= 125 -> byteArrayOf(firstByte, (maskBit or payloadSize).toByte())
+        payloadSize <= 0xffff -> byteArrayOf(
+            firstByte,
+            (maskBit or 126).toByte(),
+            ((payloadSize ushr 8) and 0xff).toByte(),
+            (payloadSize and 0xff).toByte(),
+        )
+        else -> byteArrayOf(
+            firstByte,
+            (maskBit or 127).toByte(),
+            0,
+            0,
+            0,
+            0,
+            ((payloadSize ushr 24) and 0xff).toByte(),
+            ((payloadSize ushr 16) and 0xff).toByte(),
+            ((payloadSize ushr 8) and 0xff).toByte(),
+            (payloadSize and 0xff).toByte(),
+        )
+    }
+}
+
+private fun ByteArray.toMessage(opcode: Int): LyngWsMessage = when (opcode) {
+    OPCODE_TEXT -> LyngWsMessage(isText = true, text = decodeToString())
+    OPCODE_BINARY -> LyngWsMessage(isText = false, data = copyOf())
+    else -> throw IllegalStateException("unsupported websocket opcode: $opcode")
+}
+
+private fun randomBytes(size: Int): ByteArray = ByteArray(size).also(Random.Default::nextBytes)
+
+private fun sha1(input: ByteArray): ByteArray {
+    var h0 = 0x67452301
+    var h1 = 0xEFCDAB89.toInt()
+    var h2 = 0x98BADCFE.toInt()
+    var h3 = 0x10325476
+    var h4 = 0xC3D2E1F0.toInt()
+
+    val msgLen = input.size
+    val bitLen = msgLen.toLong() * 8L
+    val totalLen = ((msgLen + 1 + 8 + 63) / 64) * 64
+    val padded = ByteArray(totalLen).also { buf ->
+        input.copyInto(buf)
+        buf[msgLen] = 0x80.toByte()
+        for (i in 0..7) {
+            buf[totalLen - 8 + i] = ((bitLen ushr (56 - i * 8)) and 0xff).toByte()
+        }
+    }
+
+    val words = IntArray(80)
+    var blockStart = 0
+    while (blockStart < padded.size) {
+        for (i in 0..15) {
+            val off = blockStart + i * 4
+            words[i] = ((padded[off].toInt() and 0xff) shl 24) or
+                ((padded[off + 1].toInt() and 0xff) shl 16) or
+                ((padded[off + 2].toInt() and 0xff) shl 8) or
+                (padded[off + 3].toInt() and 0xff)
+        }
+        for (i in 16..79) {
+            val mixed = words[i - 3] xor words[i - 8] xor words[i - 14] xor words[i - 16]
+            words[i] = (mixed shl 1) or (mixed ushr 31)
+        }
+
+        var a = h0
+        var b = h1
+        var c = h2
+        var d = h3
+        var e = h4
+
+        for (i in 0..19) {
+            val f = (b and c) or (b.inv() and d)
+            val temp = ((a shl 5) or (a ushr 27)) + f + e + 0x5A827999 + words[i]
+            e = d
+            d = c
+            c = (b shl 30) or (b ushr 2)
+            b = a
+            a = temp
+        }
+        for (i in 20..39) {
+            val f = b xor c xor d
+            val temp = ((a shl 5) or (a ushr 27)) + f + e + 0x6ED9EBA1 + words[i]
+            e = d
+            d = c
+            c = (b shl 30) or (b ushr 2)
+            b = a
+            a = temp
+        }
+        for (i in 40..59) {
+            val f = (b and c) or (b and d) or (c and d)
+            val temp = ((a shl 5) or (a ushr 27)) + f + e + 0x8F1BBCDC.toInt() + words[i]
+            e = d
+            d = c
+            c = (b shl 30) or (b ushr 2)
+            b = a
+            a = temp
+        }
+        for (i in 60..79) {
+            val f = b xor c xor d
+            val temp = ((a shl 5) or (a ushr 27)) + f + e + 0xCA62C1D6.toInt() + words[i]
+            e = d
+            d = c
+            c = (b shl 30) or (b ushr 2)
+            b = a
+            a = temp
+        }
+
+        h0 += a
+        h1 += b
+        h2 += c
+        h3 += d
+        h4 += e
+        blockStart += 64
+    }
+
+    return ByteArray(20).also { out ->
+        fun putInt(offset: Int, value: Int) {
+            out[offset] = (value ushr 24).toByte()
+            out[offset + 1] = (value ushr 16).toByte()
+            out[offset + 2] = (value ushr 8).toByte()
+            out[offset + 3] = value.toByte()
+        }
+        putInt(0, h0)
+        putInt(4, h1)
+        putInt(8, h2)
+        putInt(12, h3)
+        putInt(16, h4)
+    }
+}
+
+private const val WS_GUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
+private const val OPCODE_CONTINUATION = 0x0
+private const val OPCODE_TEXT = 0x1
+private const val OPCODE_BINARY = 0x2
+private const val OPCODE_CLOSE = 0x8
+private const val OPCODE_PING = 0x9
+private const val OPCODE_PONG = 0xA

lyngio/src/jvmTest/kotlin/net/sergeych/lyng/io/db/jdbc/LyngJdbcModuleTest.kt

@@ -112,6 +112,34 @@ class LyngJdbcModuleTest {
         assertEquals(3L, result.value)
     }
 
+    @Test
+    fun testMaterializedRowsListCanBeReturnedFromTransaction() = runTest {
+        val scope = Script.newScope()
+        createJdbcModule(scope.importManager)
+        val jdbcModule = scope.importManager.createModuleScope(Pos.builtIn, "lyng.io.db.jdbc")
+        val db = jdbcModule.callFn("openH2", ObjString("mem:rows_return_${System.nanoTime()};DB_CLOSE_DELAY=-1"))
+
+        val rows = db.invokeInstanceMethod(
+            scope,
+            "transaction",
+            ObjExternCallable.fromBridge {
+                val tx = requiredArg<Obj>(0)
+                tx.invokeInstanceMethod(
+                    requireScope(),
+                    "execute",
+                    ObjString("create table person(id bigint auto_increment primary key, name varchar(120) not null)")
+                )
+                tx.invokeInstanceMethod(requireScope(), "execute", ObjString("insert into person(name) values(?)"), ObjString("Ada"))
+                tx.invokeInstanceMethod(requireScope(), "execute", ObjString("insert into person(name) values(?)"), ObjString("Linus"))
+                tx.invokeInstanceMethod(requireScope(), "select", ObjString("select name from person order by id"))
+                    .invokeInstanceMethod(requireScope(), "toList")
+            }
+        )
+
+        assertEquals("Ada", (rows.getAt(scope, ObjInt.Zero).getAt(scope, ObjString("name")) as ObjString).value)
+        assertEquals("Linus", (rows.getAt(scope, ObjInt.of(1)).getAt(scope, ObjString("name")) as ObjString).value)
+    }
+
     private suspend fun scalarSelect(scope: net.sergeych.lyng.Scope, db: Obj, sql: String): Long {
         val result = db.invokeInstanceMethod(
             scope,

lyngio/src/jvmTest/kotlin/net/sergeych/lyng/io/db/sqlite/LyngSqliteModuleTest.kt

@@ -250,7 +250,7 @@ class LyngSqliteModuleTest {
     }
 
     @Test
-    fun testRowFailsAfterTransactionEnds() = runTest {
+    fun testMaterializedRowSurvivesAfterTransactionEnds() = runTest {
         val scope = Script.newScope()
         val db = openMemoryDb(scope)
         var leakedRow: Obj = ObjNull
@@ -265,12 +265,34 @@ class LyngSqliteModuleTest {
             }
         )
 
-        val error = assertFailsWith<ExecutionError> {
-            leakedRow.getAt(scope, ObjString("answer"))
-        }
+        val answer = leakedRow.getAt(scope, ObjString("answer")) as ObjInt
+        assertEquals(42L, answer.value)
+    }
 
-        assertEquals("SqlUsageException", error.errorObject.objClass.className)
-        assertTrue(error.errorMessage.contains("transaction is active"), error.errorMessage)
+    @Test
+    fun testMaterializedRowsListCanBeReturnedFromTransaction() = runTest {
+        val scope = Script.newScope()
+        val db = openMemoryDb(scope)
+
+        val rows = db.invokeInstanceMethod(
+            scope,
+            "transaction",
+            ObjExternCallable.fromBridge {
+                val tx = requiredArg<Obj>(0)
+                tx.invokeInstanceMethod(
+                    requireScope(),
+                    "execute",
+                    ObjString("create table items(id integer primary key autoincrement, name text not null)")
+                )
+                tx.invokeInstanceMethod(requireScope(), "execute", ObjString("insert into items(name) values(?)"), ObjString("alpha"))
+                tx.invokeInstanceMethod(requireScope(), "execute", ObjString("insert into items(name) values(?)"), ObjString("beta"))
+                tx.invokeInstanceMethod(requireScope(), "select", ObjString("select name from items order by id"))
+                    .invokeInstanceMethod(requireScope(), "toList")
+            }
+        )
+
+        assertEquals("alpha", stringValue(scope, rows.getAt(scope, ObjInt.Zero).getAt(scope, ObjString("name"))))
+        assertEquals("beta", stringValue(scope, rows.getAt(scope, ObjInt.of(1)).getAt(scope, ObjString("name"))))
     }
 
     @Test

lyngio/src/linuxMain/kotlin/net/sergeych/lyngio/ws/PlatformLinux.kt

@@ -2,4 +2,5 @@ package net.sergeych.lyngio.ws
 
 import io.ktor.client.engine.curl.Curl
 
-actual fun getSystemWsEngine(): LyngWsEngine = createKtorWsEngine(Curl)
+actual fun getSystemWsEngine(): LyngWsEngine =
+    createSocketWsEngine(secureFallback = createKtorWsEngine(Curl, shareClient = false))

lyngio/src/linuxTest/kotlin/net/sergeych/lyng/io/db/sqlite/LyngSqliteModuleNativeTest.kt

@@ -186,7 +186,7 @@ class LyngSqliteModuleNativeTest {
     }
 
     @Test
-    fun testRowFailsAfterTransactionEnds() = runTest {
+    fun testMaterializedRowSurvivesAfterTransactionEnds() = runTest {
         val scope = Script.newScope()
         val db = openMemoryDb(scope)
         var leakedRow: Obj = ObjNull
@@ -201,12 +201,34 @@ class LyngSqliteModuleNativeTest {
             }
         )
 
-        val error = assertFailsWith<ExecutionError> {
-            leakedRow.getAt(scope, ObjString("answer"))
-        }
+        val answer = leakedRow.getAt(scope, ObjString("answer")) as ObjInt
+        assertEquals(42L, answer.value)
+    }
 
-        assertEquals("SqlUsageException", error.errorObject.objClass.className)
-        assertTrue(error.errorMessage.contains("transaction is active"), error.errorMessage)
+    @Test
+    fun testMaterializedRowsListCanBeReturnedFromTransaction() = runTest {
+        val scope = Script.newScope()
+        val db = openMemoryDb(scope)
+
+        val rows = db.invokeInstanceMethod(
+            scope,
+            "transaction",
+            ObjExternCallable.fromBridge {
+                val tx = requiredArg<Obj>(0)
+                tx.invokeInstanceMethod(
+                    requireScope(),
+                    "execute",
+                    ObjString("create table items(id integer primary key autoincrement, name text not null)")
+                )
+                tx.invokeInstanceMethod(requireScope(), "execute", ObjString("insert into items(name) values(?)"), ObjString("alpha"))
+                tx.invokeInstanceMethod(requireScope(), "execute", ObjString("insert into items(name) values(?)"), ObjString("beta"))
+                tx.invokeInstanceMethod(requireScope(), "select", ObjString("select name from items order by id"))
+                    .invokeInstanceMethod(requireScope(), "toList")
+            }
+        )
+
+        assertEquals("alpha", stringValue(scope, rows.getAt(scope, ObjInt.Zero).getAt(scope, ObjString("name"))))
+        assertEquals("beta", stringValue(scope, rows.getAt(scope, ObjInt.of(1)).getAt(scope, ObjString("name"))))
     }
 
     @Test

lyngio/stdlib/lyng/io/db.lyng

@@ -44,11 +44,11 @@ extern class SqlRow {
     - iteration to the end or canceled iteration should close the underlying
       resources automatically
     - using the result set after its transaction ends is invalid
-    - rows obtained from the result set are also invalid after the owning
-      transaction ends, even if the implementation had already buffered them
+    - rows obtained from the result set stay usable after the owning
+      transaction ends once they have been materialized
 
-    If user code wants row data to survive independently, it should copy the
-    values it needs into ordinary Lyng objects while the transaction is active.
+    Calling `toList()` while the transaction is active is the normal way to
+    detach rows for use after the transaction block returns.
 */
 extern class ResultSet : Iterable<SqlRow> {
     /*
@@ -84,7 +84,8 @@ extern class ExecutionResult {
         other result set.
 
         If the statement produced no generated values, the returned result set
-        is empty.
+        is empty. Call `toList()` if generated-key rows must outlive the
+        transaction.
     */
     fun getGeneratedKeys(): ResultSet
 }

lynglib/src/commonMain/kotlin/net/sergeych/lyng/Compiler.kt

@@ -10679,8 +10679,12 @@ class Compiler(
                 )
             }
             if (getter != null || setter != null) {
-                val prop = ObjProperty(name, getter, setter)
-                val initStmt = if (!isAbstract) {
+                val prop = if (actualExtern) {
+                    ObjProperty(name, null, null)
+                } else {
+                    ObjProperty(name, getter, setter)
+                }
+                val initStmt = if (!isAbstract && !actualExtern) {
                     val initStatement = InstancePropertyInitStatement(
                         storageName = storageName,
                         isMutable = isMutable,

lynglib/src/commonMain/kotlin/net/sergeych/lyng/obj/ObjBindingSupport.kt

@@ -0,0 +1,62 @@
+package net.sergeych.lyng.obj
+
+import net.sergeych.lyng.ScopeFacade
+import net.sergeych.lyng.requiredArg
+
+internal fun ObjClass.bindClassFn(name: String, code: suspend ScopeFacade.() -> Obj) {
+    val callable = ObjExternCallable.fromBridge { code() }
+    val memberRecord = members[name]
+    val classScopeRecord = classScope?.objects?.get(name)
+    if (memberRecord != null) {
+        val methodId = ensureMethodIdForBridge(name, memberRecord)
+        val newRecord = memberRecord.copy(
+            value = callable,
+            type = ObjRecord.Type.Fun,
+            methodId = methodId,
+            isAbstract = false,
+        )
+        replaceMemberForBridge(name, newRecord)
+        if (classScopeRecord != null) {
+            replaceClassScopeMemberForBridge(name, newRecord)
+        }
+    } else if (classScopeRecord != null) {
+        val methodId = ensureMethodIdForBridge(name, classScopeRecord)
+        replaceClassScopeMemberForBridge(
+            name,
+            classScopeRecord.copy(
+                value = callable,
+                type = ObjRecord.Type.Fun,
+                methodId = methodId,
+                isAbstract = false,
+            )
+        )
+    } else {
+        addClassFn(name, code = code)
+    }
+}
+
+internal fun ObjClass.bindProperty(
+    name: String,
+    getter: (suspend ScopeFacade.() -> Obj)? = null,
+    setter: (suspend ScopeFacade.(Obj) -> Unit)? = null,
+) {
+    val g = getter?.let { ObjExternCallable.fromBridge { it() } }
+    val s = setter?.let { ObjExternCallable.fromBridge { it(requiredArg(0)); ObjVoid } }
+    val prop = ObjProperty(name, g, s)
+    val existing = members[name]
+    if (existing != null) {
+        val newRecord = existing.copy(
+            value = prop,
+            type = ObjRecord.Type.Property,
+            methodId = ensureMethodIdForBridge(name, existing),
+            fieldId = null,
+            isAbstract = false,
+        )
+        replaceMemberForBridge(name, newRecord)
+        if (classScope?.objects?.containsKey(name) == true) {
+            replaceClassScopeMemberForBridge(name, newRecord)
+        }
+    } else {
+        addProperty(name, getter = getter, setter = setter)
+    }
+}

lynglib/src/commonMain/kotlin/net/sergeych/lyng/obj/ObjComplexSupport.kt

@@ -18,13 +18,10 @@
 package net.sergeych.lyng.obj
 
 import net.sergeych.lyng.*
-import net.sergeych.lyng.miniast.addPropertyDoc
-import net.sergeych.lyng.miniast.type
 import net.sergeych.lyng.requiredArg
 
 object ObjComplexSupport {
     private object BoundMarker
-    private val complexTypeDecl = TypeDecl.Simple("lyng.complex.Complex", false)
 
     suspend fun bindTo(module: ModuleScope) {
         val complexClass = module.requireClass("Complex")
@@ -33,36 +30,20 @@ object ObjComplexSupport {
 
         val decimalModule = module.currentImportProvider.createModuleScope(module.pos, "lyng.decimal")
         val decimalClass = decimalModule.requireClass("Decimal")
-
-        decimalClass.addPropertyDoc(
-            name = "re",
-            doc = "Convert this Decimal to a Complex with zero imaginary part.",
-            type = type("lyng.complex.Complex"),
-            moduleName = "lyng.complex",
-            getter = {
-                newComplex(
-                    complexClass,
-                    decimalToReal(thisObj),
-                    0.0
-                )
-            }
-        )
-        decimalClass.members["re"] = decimalClass.members.getValue("re").copy(typeDecl = complexTypeDecl)
-
-        decimalClass.addPropertyDoc(
-            name = "i",
-            doc = "Convert this Decimal to a pure imaginary Complex after rounding to Real.",
-            type = type("lyng.complex.Complex"),
-            moduleName = "lyng.complex",
-            getter = {
-                newComplex(
-                    complexClass,
-                    0.0,
-                    decimalToReal(thisObj)
-                )
-            }
-        )
-        decimalClass.members["i"] = decimalClass.members.getValue("i").copy(typeDecl = complexTypeDecl)
+        decimalClass.bindProperty("re", getter = {
+            newComplex(
+                complexClass,
+                decimalToReal(thisObj),
+                0.0
+            )
+        })
+        decimalClass.bindProperty("i", getter = {
+            newComplex(
+                complexClass,
+                0.0,
+                decimalToReal(thisObj)
+            )
+        })
 
         OperatorInteropRegistry.register(
             leftClass = decimalClass,

lynglib/src/commonMain/kotlin/net/sergeych/lyng/obj/ObjDecimalSupport.kt

@@ -106,15 +106,15 @@ object ObjDecimalSupport {
         decimalClass.addFn("toStringExpanded") {
             ObjString(valueOf(thisObj).toStringExpanded())
         }
-        decimalClass.addClassFn("fromInt") {
+        decimalClass.bindClassFn("fromInt") {
             val value = requiredArg<ObjInt>(0).value
             newInstance(decimalClass, IonBigDecimal.fromLong(value))
         }
-        decimalClass.addClassFn("fromReal") {
+        decimalClass.bindClassFn("fromReal") {
             val value = requiredArg<ObjReal>(0).value
             newInstanceFromFiniteReal(decimalClass, value)
         }
-        decimalClass.addClassFn("fromString") {
+        decimalClass.bindClassFn("fromString") {
             val value = requiredArg<ObjString>(0).value
             try {
                 newInstance(decimalClass, IonBigDecimal.parseStringWithMode(value))

lynglib/src/commonMain/kotlin/net/sergeych/lyng/obj/ObjMatrixSupport.kt

@@ -53,10 +53,10 @@ object ObjMatrixSupport {
         }
         hooks += { _, instance -> instance.kotlinInstanceData = defaultVector }
 
-        vectorClass.addProperty("size", getter = {
+        vectorClass.bindProperty("size", getter = {
             ObjInt.of(vectorOf(thisObj).size.toLong())
         })
-        vectorClass.addProperty("length", getter = {
+        vectorClass.bindProperty("length", getter = {
             ObjInt.of(vectorOf(thisObj).size.toLong())
         })
         vectorClass.addFn("toList") {
@@ -99,10 +99,10 @@ object ObjMatrixSupport {
             ObjInt.of(vectorOf(thisObj).compareTo(coerceVectorArg(requireScope(), args.firstAndOnly())).toLong())
         }
 
-        vectorClass.addClassFn("fromList") {
+        vectorClass.bindClassFn("fromList") {
             newVector(vectorClass, parseVector(requireScope(), requiredArg(0)))
         }
-        vectorClass.addClassFn("zeros") {
+        vectorClass.bindClassFn("zeros") {
             val size = requiredArg<ObjInt>(0).value.toInt()
             if (size <= 0) requireScope().raiseIllegalArgument("vector size must be positive")
             newVector(vectorClass, VectorData(DoubleArray(size)))
@@ -119,13 +119,13 @@ object ObjMatrixSupport {
         }
         hooks += { _, instance -> instance.kotlinInstanceData = defaultMatrix }
 
-        matrixClass.addProperty("rows", getter = {
+        matrixClass.bindProperty("rows", getter = {
             ObjInt.of(matrixOf(thisObj).rows.toLong())
         })
-        matrixClass.addProperty("cols", getter = {
+        matrixClass.bindProperty("cols", getter = {
             ObjInt.of(matrixOf(thisObj).cols.toLong())
         })
-        matrixClass.addProperty("shape", getter = {
+        matrixClass.bindProperty("shape", getter = {
             ObjList(
                 mutableListOf(
                     ObjInt.of(matrixOf(thisObj).rows.toLong()),
@@ -133,7 +133,7 @@ object ObjMatrixSupport {
                 )
             )
         })
-        matrixClass.addProperty("isSquare", getter = {
+        matrixClass.bindProperty("isSquare", getter = {
             matrixOf(thisObj).isSquare.toObj()
         })
 
@@ -208,17 +208,17 @@ object ObjMatrixSupport {
             ObjInt.of(matrixOf(thisObj).compareTo(coerceMatrixArg(requireScope(), args.firstAndOnly())).toLong())
         }
 
-        matrixClass.addClassFn("fromRows") {
+        matrixClass.bindClassFn("fromRows") {
             newMatrix(matrixClass, parseRows(requireScope(), requiredArg(0)))
         }
-        matrixClass.addClassFn("zeros") {
+        matrixClass.bindClassFn("zeros") {
             val rows = requiredArg<ObjInt>(0).value.toInt()
             val cols = requiredArg<ObjInt>(1).value.toInt()
             if (rows <= 0) requireScope().raiseIllegalArgument("matrix must have at least one row")
             if (cols <= 0) requireScope().raiseIllegalArgument("matrix must have at least one column")
             newMatrix(matrixClass, MatrixData(rows, cols, DoubleArray(rows * cols)))
         }
-        matrixClass.addClassFn("identity") {
+        matrixClass.bindClassFn("identity") {
             val size = requiredArg<ObjInt>(0).value.toInt()
             if (size <= 0) requireScope().raiseIllegalArgument("identity matrix size must be positive")
             val values = DoubleArray(size * size)

lynglib/src/commonMain/kotlin/net/sergeych/lyng/stdlib_included/decimal_lyng.kt

@@ -201,14 +201,7 @@ extern class Decimal() {
  *
  * Contexts are dynamic and block-local. After the block finishes, the previous context is restored.
  */
-extern fun withDecimalContext<T>(context: DecimalContext, block: ()->T): T
-
-/**
- * Convenience overload for changing only precision.
- *
- * Equivalent to `withDecimalContext(DecimalContext(precision, DecimalRounding.HalfEven), block)`.
- */
-extern fun withDecimalContext<T>(precision: Int, block: ()->T): T
+extern fun withDecimalContext<T>(context: Object, block: ()->T): T
 
 /**
  * Convenience overload for changing precision and rounding explicitly.

lynglib/src/commonTest/kotlin/net/sergeych/lyng/DecimalModuleTest.kt

@@ -205,10 +205,8 @@ class DecimalModuleTest {
             assertEquals("0.3333333333333333333333333333333333", (1.d / 3.d).toStringExpanded())
             assertEquals("0.3333333333", withDecimalContext(10) { (1.d / 3.d).toStringExpanded() })
             assertEquals("0.666667", withDecimalContext(6) { ("2".d / 3.d).toStringExpanded() })
-            assertEquals("0.666667", withDecimalContext(DecimalContext(6)) { ("2".d / 3.d).toStringExpanded() })
             assertEquals("0.12", withDecimalContext(2) { (1.d / 8.d).toStringExpanded() })
             assertEquals("0.13", withDecimalContext(2, DecimalRounding.HalfAwayFromZero) { (1.d / 8.d).toStringExpanded() })
-            assertEquals("0.13", withDecimalContext(DecimalContext(2, DecimalRounding.HalfAwayFromZero)) { (1.d / 8.d).toStringExpanded() })
             assertEquals("0.3333333333333333333333333333333333", (1.d / 3.d).toStringExpanded())
             """.trimIndent()
         )

lynglib/src/nativeMain/kotlin/net/sergeych/lyng/PerfDefaults.native.kt

@@ -23,7 +23,7 @@ actual object PerfDefaults {
 
     actual val ARG_BUILDER: Boolean = true
     actual val SKIP_ARGS_ON_NULL_RECEIVER: Boolean = true
-    actual val SCOPE_POOL: Boolean = true
+    actual val SCOPE_POOL: Boolean = false
 
     actual val FIELD_PIC: Boolean = true
     actual val METHOD_PIC: Boolean = true

lynglib/stdlib/lyng/complex.lyng

@@ -1,5 +1,6 @@
 package lyng.complex
 
+import lyng.decimal
 import lyng.operators
 
 /*
@@ -112,8 +113,10 @@ fun cis(angle: Real): Complex = Complex.fromPolar(1.0, angle)
 
 val Int.re: Complex get() = Complex.fromInt(this)
 val Real.re: Complex get() = Complex.fromReal(this)
+val Decimal.re: Complex get() = Complex(this.toReal(), 0.0)
 val Int.i: Complex get() = Complex.imaginary(this + 0.0)
 val Real.i: Complex get() = Complex.imaginary(this)
+val Decimal.i: Complex get() = Complex(0.0, this.toReal())
 
 OperatorInterop.register(
     Int,

lynglib/stdlib/lyng/matrix.lyng

@@ -6,9 +6,11 @@ type MatrixScalar = Real | Int
 extern class Vector() {
     /** Number of elements. */
     val size: Int
+        get() = 0
 
     /** Alias to `size`. */
     val length: Int
+        get() = 0
 
     /** Convert to a plain list. */
     extern fun toList(): List<Real>
@@ -61,15 +63,19 @@ extern class Vector() {
 extern class Matrix() {
     /** Number of rows. */
     val rows: Int
+        get() = 0
 
     /** Number of columns. */
     val cols: Int
+        get() = 0
 
     /** Two-element shape `[rows, cols]`. */
     val shape: List<Int>
+        get() = []
 
     /** Whether `rows == cols`. */
     val isSquare: Bool
+        get() = false
 
     /** Element-wise addition. Shapes must match. */
     extern fun plus(other: Matrix): Matrix

notes/db/db_interface.md

@@ -61,10 +61,10 @@ Notes:
   rather than silently degrading to some other visible type.
 - `ResultSet` should stay iterable, but also expose `isEmpty()` for cheap
   emptiness checks where possible and `size()` as a separate operation.
-- `ResultSet` and all `SqlRow` instances obtained from it are valid only while
-  the owning transaction is active. After transaction end, any further row or
-  result-set access should fail with `SqlUsageException`, even if the provider
-  had buffered data internally.
+- `ResultSet` is valid only while the owning transaction is active.
+- Materialized `SqlRow` values should be detached snapshots, so
+  `transaction { tx.select(...).toList() }` is a valid pattern and the rows
+  remain usable after transaction end.
 - Portable SQL parameter values should match the row conversion set: `null`,
   `Bool`, `Int`, `Double`, `Decimal`, `String`, `Buffer`,
   `Date`, `DateTime`, and `Instant`.

notes/db/lyngdb.lyng

@@ -42,11 +42,11 @@ class SqlRow(
     - iteration to the end or canceled iteration should close the underlying
       resources automatically
     - using the result set after its transaction ends is invalid
-    - rows obtained from the result set are also invalid after the owning
-      transaction ends, even if the implementation had already buffered them
+    - rows obtained from the result set stay usable after the owning
+      transaction ends once they have been materialized
 
-    If user code wants row data to survive independently, it should copy the
-    values it needs into ordinary Lyng objects while the transaction is active.
+    Calling [toList] while the transaction is active is the normal way to
+    detach rows for use after the transaction block returns.
 */
 interface ResultSet : Iterable<SqlRow> {
     /*

notes/db/sqlite_provider.md

@@ -96,8 +96,8 @@ row-id behavior are all connection-local.
 The provider may stream rows or buffer them, but it must preserve the core
 contract:
 - result sets are valid only while the owning transaction is active
-- rows obtained from a result set are also invalid after the owning
-  transaction ends, even if they were already buffered
+- rows obtained from a result set should stay usable after the owning
+  transaction ends once they were materialized, e.g. with `toList()`
 - iteration closes underlying resources when finished or canceled
 - `isEmpty()` should be cheap where possible
 - `size()` may consume or buffer the full result