closure tests and fix

docs/advanced_topics.md

@@ -0,0 +1,50 @@
+# Advanced topics
+
+## Closures/scopes isolation
+
+Each block has own scope, in which it can safely uses closures and override
+outer vars:
+
+    var param = "global"
+    val prefix = "param in "
+    val scope1 = {
+        var param = prefix + "scope1"
+        param
+    }
+    val scope2 = {
+        var param = prefix + "scope2"
+        param
+    }
+    // note that block returns its last value
+    println(scope1)
+    println(scope2)
+    println(param)
+    >>> param in scope1
+    >>> param in scope2
+    >>> global
+    >>> void
+
+One interesting way of using closure isolation is to keep state of the functions:
+
+    val getAndIncrement = {
+        // will be updated by doIt()
+        var counter = 0
+
+        // we return callable fn from the block:
+        fun doit() {
+            val was = counter
+            counter = counter + 1
+            was
+        }
+    }
+    println(getAndIncrement())
+    println(getAndIncrement())
+    println(getAndIncrement())
+    >>> 0
+    >>> 1
+    >>> 2
+    >>> void
+
+Inner `counter` is not accessible from outside, no way; still it is kept 
+between calls in the closure, as inner function `doit`, returned from the
+block, keeps reference to it and keeps it alive.

docs/math.md

@@ -11,10 +11,10 @@ Same as in C++.
 |        2         | `+` `-`                              |
 |        3         | bit shifts (NI)                      |
 |        4         | `<=>` (NI)                           |
-|        5         | `<=` `>=` `<` `>` (NI)               |
-|        6         | `==` `!=` (NI)                       |
-|        7         | `&` (NI)                             |
-|        9         | `\|` (NI)                            |
+|        5         | `<=` `>=` `<` `>`                    |
+|        6         | `==` `!=`                            |
+|        7         | bitwise and `&` (NI)                 |
+|        9         | bitwise or `\|` (NI)                 |
 |        10        | `&&`                                 |
 |  11<br/>lowest   | `\|\|`                               |
 
@@ -22,7 +22,16 @@ Same as in C++.
 
 ## Operators
 
-`+ - * / % `: if both operand is `Int`, calculates as int. Otherwise, as real.
+`+ - * / % `: if both operand is `Int`, calculates as int. Otherwise, as real:
+
+    // integer division:
+    3 / 2
+    >>> 1
+
+but:
+
+    3 / 2.0
+    >>> 1.5
 
 ## Round and range
 
@@ -46,6 +55,11 @@ or transformed `Real` otherwise.
 |                     |         |
 |                     |         |
 
+For example: 
+
+    sin(π/2)
+    >>> 1.0
+
 ## Scientific constant
 
 | name                 | meaning      |

docs/tutorial.md

@@ -154,14 +154,20 @@ Each __block has an isolated context that can be accessed from closures__. For e
     }
     >>> void
 
-As was told, `def` statement return callable for the function, it could be used as a parameter, or elsewhere
+As was told, `fun` statement return callable for the function, it could be used as a parameter, or elsewhere
 to call it:
 
+    val taskAlias = fun someTask() {
+        println("Hello")
+    }
     // call the callable stored in the var
     taskAlias()
     // or directly:
     someTask()
-    
+    >>> Hello
+    >>> Hello
+    >>> void
+
 If you need to create _unnamed_ function, use alternative syntax (TBD, like { -> } ?)
 
 # Flow control operators
@@ -276,8 +282,12 @@ We can skip the rest of the loop and restart it, as usual, with `continue` opera
 
 Notice that `total` remains 0 as the end of the outerLoop@ is not reachable: `continue` is always called and always make Ling to skip it.
 
+## Labels@
+
 The label can be any valid identifier, even a keyword, labels exist in their own, isolated world, so no risk of occasional clash. Labels are also scoped to their context and do not exist outside it.
 
+Right now labels are implemented only for the while loop. It is intended to be implemented for all loops and returns.
+
 # Comments
 
     // single line comment
@@ -296,6 +306,8 @@ The label can be any valid identifier, even a keyword, labels exist in their own
 | Null   | missing value, singleton        | null                |
 | Fn     | callable type                   |                     |
 
+See also [math operations](math.md)
+
 ## String details
 
 ### String operations

library/src/commonMain/kotlin/net/sergeych/ling/Compiler.kt

@@ -498,11 +498,16 @@ class Compiler {
         // Here we should be at open body
         val fnStatements = parseBlock(tokens)
 
-        val fnBody = statement(t.pos) { context ->
-            // load params
+        var closure: Context? = null
+
+        val fnBody = statement(t.pos) { callerContext ->
+            // remember closure where the function was defined:
+            val context = closure ?: Context()
+            // load params from caller context
+            println("calling function $name in context $context <- ${context.parent}")
             for ((i, d) in params.withIndex()) {
-                if (i < context.args.size)
-                    context.addItem(d.name, false, context.args.list[i].value)
+                if (i < callerContext.args.size)
+                    context.addItem(d.name, false, callerContext.args.list[i].value)
                 else
                     context.addItem(
                         d.name,
@@ -514,10 +519,12 @@ class Compiler {
                             )
                     )
             }
-
+            // save closure
             fnStatements.execute(context)
         }
         return statement(start) { context ->
+            println("adding function $name to context $context")
+            closure = context
             context.addItem(name, false, fnBody)
             fnBody
         }

library/src/commonMain/kotlin/net/sergeych/ling/Context.kt

@@ -5,24 +5,21 @@ class Context(
     val args: Arguments = Arguments.EMPTY
 ) {
 
-    data class Item(
-        val name: String,
-        var value: Obj?,
-        val isMutable: Boolean = false
-    )
+    private val objects = mutableMapOf<String, StoredObj>()
 
-    private val objects = mutableMapOf<String, Item>()
-
-    operator fun get(name: String): Item? = objects[name] ?: parent?.get(name)
+    operator fun get(name: String): StoredObj? =
+        objects[name]
+            ?: parent?.get(name)
 
     fun copy(args: Arguments = Arguments.EMPTY): Context = Context(this, args)
 
     fun addItem(name: String, isMutable: Boolean, value: Obj?) {
-        objects.put(name, Item(name, value, isMutable))
+        println("ading item $name=$value in $this <- ${this.parent}")
+        objects.put(name, StoredObj(name, value, isMutable))
     }
 
     fun getOrCreateNamespace(name: String) =
-        (objects.getOrPut(name) { Item(name, ObjNamespace(name,copy()), isMutable = false) }.value as ObjNamespace)
+        (objects.getOrPut(name) { StoredObj(name, ObjNamespace(name,copy()), isMutable = false) }.value as ObjNamespace)
             .context
 
     inline fun <reified T> addFn(vararg names: String, crossinline fn: suspend Context.() -> T) {

library/src/commonMain/kotlin/net/sergeych/ling/Obj.kt

@@ -1,33 +1,77 @@
 package net.sergeych.ling
 
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import kotlin.math.floor
 
+typealias InstanceMethod = (Context, Obj) -> Obj
+
+data class Item<T>(var value: T, val isMutable: Boolean = false)
+
+@Serializable
+sealed class ClassDef(
+    val className: String
+) {
+    val baseClasses: List<ClassDef> get() = emptyList()
+    private val instanceMethods: MutableMap<String, Item<InstanceMethod>> get() = mutableMapOf()
+
+    private val instanceLock = Mutex()
+
+    suspend fun addInstanceMethod(
+        name: String,
+        freeze: Boolean = false,
+        pos: Pos = Pos.builtIn,
+        body: InstanceMethod
+    ) {
+        instanceLock.withLock {
+            instanceMethods[name]?.let {
+                if( !it.isMutable )
+                    throw ScriptError(pos, "existing method $name is frozen and can't be updated")
+                it.value = body
+            } ?: instanceMethods.put(name, Item(body, freeze))
+        }
+    }
+
+    //suspend fun callInstanceMethod(context: Context, self: Obj,args: Arguments): Obj {
+//
+  //  }
+}
+
+object ObjClassDef : ClassDef("Obj")
+
 @Serializable
 sealed class Obj : Comparable<Obj> {
     open val asStr: ObjString by lazy {
         if (this is ObjString) this else ObjString(this.toString())
     }
 
-    open val type: Type = Type.Any
+    open val definition: ClassDef = ObjClassDef
 
     @Suppress("unused")
     enum class Type {
         @SerialName("Void")
         Void,
+
         @SerialName("Null")
         Null,
+
         @SerialName("String")
         String,
+
         @SerialName("Int")
         Int,
+
         @SerialName("Real")
         Real,
+
         @SerialName("Bool")
         Bool,
+
         @SerialName("Fn")
         Fn,
+
         @SerialName("Any")
         Any,
     }
@@ -112,7 +156,8 @@ fun Obj.toLong(): Long =
 
 fun Obj.toInt(): Int = toLong().toInt()
 
-fun Obj.toBool(): Boolean = (this as? ObjBool)?.value ?: throw IllegalArgumentException("cannot convert to boolean ${this.type}:$this")
+fun Obj.toBool(): Boolean =
+    (this as? ObjBool)?.value ?: throw IllegalArgumentException("cannot convert to boolean $this")
 
 
 @Serializable
@@ -125,7 +170,7 @@ data class ObjReal(val value: Double) : Obj(), Numeric {
     override val toObjReal: ObjReal by lazy { ObjReal(value) }
 
     override fun compareTo(other: Obj): Int {
-        if( other !is Numeric) throw IllegalArgumentException("cannot compare $this with $other")
+        if (other !is Numeric) throw IllegalArgumentException("cannot compare $this with $other")
         return value.compareTo(other.doubleValue)
     }
 
@@ -142,7 +187,7 @@ data class ObjInt(val value: Long) : Obj(), Numeric {
     override val toObjReal: ObjReal by lazy { ObjReal(doubleValue) }
 
     override fun compareTo(other: Obj): Int {
-        if( other !is Numeric) throw IllegalArgumentException("cannot compare $this with $other")
+        if (other !is Numeric) throw IllegalArgumentException("cannot compare $this with $other")
         return value.compareTo(other.doubleValue)
     }
 
@@ -155,9 +200,10 @@ data class ObjBool(val value: Boolean) : Obj() {
     override val asStr by lazy { ObjString(value.toString()) }
 
     override fun compareTo(other: Obj): Int {
-        if( other !is ObjBool) throw IllegalArgumentException("cannot compare $this with $other")
+        if (other !is ObjBool) throw IllegalArgumentException("cannot compare $this with $other")
         return value.compareTo(other.value)
     }
+
     override fun toString(): String = value.toString()
 }
 

library/src/commonMain/kotlin/net/sergeych/ling/Script.kt

@@ -9,6 +9,7 @@ class Script(
 
     override suspend fun execute(context: Context): Obj {
         // todo: run script
+        println("exec script in $context <- ${context.parent}")
         var lastResult: Obj = ObjVoid
         for (s in statements) {
             lastResult = s.execute(context)

library/src/commonMain/kotlin/net/sergeych/ling/StoredObj.kt

@@ -0,0 +1,10 @@
+package net.sergeych.ling
+
+/**
+ * Whatever [Obj] stored somewhere
+ */
+data class StoredObj(
+    val name: String,
+    var value: Obj?,
+    val isMutable: Boolean = false
+)

library/src/jvmTest/kotlin/BookTest.kt

@@ -34,22 +34,21 @@ data class DocTest(
     val sourceLines by lazy { code.lines() }
 
     override fun toString(): String {
-        return "DocTest:$fileName:${line+1}..${line + sourceLines.size}"
+        return "DocTest:$fileName:${line + 1}..${line + sourceLines.size}"
     }
 
     val detailedString by lazy {
         val codeWithLines = sourceLines.withIndex().map { (i, s) -> "${i + line}: $s" }.joinToString("\n")
-        "$this\n" +
-                codeWithLines + "\n" +
-                "--------expected output--------\n" +
-                expectedOutput +
-                "-----expected return value-----\n" +
-                expectedResult
+        var result = "$this\n$codeWithLines\n"
+        if (expectedOutput.isNotBlank())
+            result += "--------expected output--------\n$expectedOutput\n"
+
+        "$result-----expected return value-----\n$expectedResult"
     }
 }
 
-fun parseDocTests(name: String): Flow<DocTest> = flow {
-    val book = readAllLines(Paths.get("../docs/tutorial.md"))
+fun parseDocTests(fileName: String): Flow<DocTest> = flow {
+    val book = readAllLines(Paths.get(fileName))
     var startOffset = 0
     val block = mutableListOf<String>()
     var startIndex = 0
@@ -94,10 +93,10 @@ fun parseDocTests(name: String): Flow<DocTest> = flow {
                             if (isValid) {
                                 emit(
                                     DocTest(
-                                        name, startIndex,
+                                        fileName, startIndex,
                                         block.joinToString("\n"),
                                         if (result.size > 1)
-                                            result.dropLast(1).joinToString { it + "\n" }
+                                            result.dropLast(1).joinToString("") { it + "\n" }
                                         else "",
                                         result.last()
                                     )
@@ -149,8 +148,7 @@ suspend fun DocTest.test() {
     var error: Throwable? = null
     val result = try {
         context.eval(code)
-    }
-    catch (e: Throwable) {
+    } catch (e: Throwable) {
         error = e
         null
     }?.toString()?.replace(Regex("@\\d+"), "@...")
@@ -166,12 +164,27 @@ suspend fun DocTest.test() {
     //    println("OK: $this")
 }
 
+suspend fun runDocTests(fileName: String) {
+    parseDocTests(fileName).collect { dt ->
+        dt.test()
+    }
+
+}
+
 class BookTest {
 
     @Test
     fun testsFromTutorial() = runTest {
-        parseDocTests("../docs/tutorial.md").collect { dt ->
-            dt.test()
-        }
+        runDocTests("../docs/tutorial.md")
+    }
+
+    @Test
+    fun testsFromMath() = runTest {
+        runDocTests("../docs/math.md")
+    }
+
+    @Test
+    fun testsFromAdvanced() = runTest {
+        runDocTests("../docs/advanced_topics.md")
     }
 }