fix #34 minimal time manipulation

docs/time.md

@@ -0,0 +1,123 @@
+# Lyng time functions
+
+Lyng date and time support requires importing `lyng.time` packages. Lyng uses simple yet modern time object models:
+
+- `Instant` class for time stamps with platform-dependent resolution
+- `Duration` to represent amount of time not depending on the calendar, e.g. in absolute units (milliseconds, seconds, hours, days)
+
+## Time instant: `Instant`
+
+Represent some moment of time not depending on the calendar (calendar for example may b e changed, daylight saving time can be for example introduced or dropped). It is similar to `TIMESTAMP` in SQL or `Instant` in Kotlin. Some moment of time; not the calendar date.
+
+Instant is comparable to other Instant. Subtracting instants produce `Duration`, period in time that is not dependent on the calendar, e.g. absolute time period.
+
+It is possible to add or subtract `Duration` to and from `Instant`, that gives another `Instant`.
+
+Instants are converted to and from `Real` number of seconds before or after Unix Epoch, 01.01.1970. Constructor with single number parameter constructs from such number of seconds,
+and any instance provide `.epochSeconds` member:
+
+    import lyng.time
+
+    // default constructor returns time now:
+    val t1 = Instant()
+    val t2 = Instant()
+    assert( t2 - t1 < 1.millisecond )
+    assert( t2.epochSeconds - t1.epochSeconds < 0.001 )
+    >>> void
+
+## Constructing
+
+    import lyng.time
+
+    // empty constructor gives current time instant using system clock:
+    val now = Instant()
+
+    // constructor with Instant instance makes a copy:
+    assertEquals( now, Instant(now) )
+
+    // constructing from a number is trated as seconds since unix epoch:
+    val copyOfNow = Instant( now.epochSeconds )
+
+    // note that instant resolution is higher that Real can hold
+    // so reconstructed from real slightly differs:
+    assert( abs( (copyOfNow - now).milliseconds ) < 0.01 )
+    >>> void
+
+The resolution of system clock could be more precise and double precision real number of `Real`, keep it in mind.
+
+## Comparing and calculating periods
+
+    import lyng.time
+    
+    val now = Instant()
+    
+    // you cam add or subtract periods, and compare
+    assert( now - 5.minutes < now )
+    val oneHourAgo = now - 1.hour
+    assertEquals( now, oneHourAgo + 1.hour)
+
+    >>> void
+
+## Instant members
+
+| member                | description                                             |
+|-----------------------|---------------------------------------------------------|
+| epochSeconds: Real    | positive or negative offset in seconds since Unix epoch |
+| isDistantFuture: Bool | true if it `Instant.distantFuture`                      |
+| isDistantPast: Bool   | true if it `Instant.distantPast`                        |
+
+## Class members
+
+| member                         | description                                             |
+|--------------------------------|---------------------------------------------------------|
+| Instant.distantPast: Instant   | most distant instant in past                            |
+| Instant.distantFuture: Instant | most distant instant in future                          |
+
+# `Duraion` class
+
+Represent absolute time distance between two `Instant`.
+
+    import lyng.time
+    val t1 = Instant()
+
+    // yes we can delay to period, and it is not blocking. is suspends!
+    delay(1.millisecond)
+
+    val t2 = Instant()
+    // be suspend, so actual time may vary:
+    assert( t2 - t1 >= 1.millisecond)
+    assert( t2 - t1 < 100.millisecond)
+    >>> void
+
+Duration can be converted from numbers, like `5.minutes` and so on. Extensions are created for
+`Int` and `Real`, so for n as Real or Int it is possible to create durations::
+
+- `n.millisecond`, `n.milliseconds`
+- `n.second`, `n.seconds`
+- `n.minute`, `n.minutes`
+- `n.hour`, `n.hours`
+- `n.day`, `n.days`
+
+The bigger time units like months or years are calendar-dependent and can't be used with `Duration`.
+
+Each duration instance can be converted to number of any of these time units, as `Real` number, if `d` is a `Duration` instance:
+
+- `d.milliseconds`
+- `d.seconds`
+- `d.minutes`
+- `d.hours`
+- `d.days`
+
+for example
+
+    import lyng.time
+    assertEquals( 60, 1.minute.seconds )
+    >>> void
+
+# Utility functions
+
+## delay(duration: Duration)
+
+Suspends current coroutine for at least the specified duration.
+
+

docs/tutorial.md

@@ -14,7 +14,7 @@ __Other documents to read__ maybe after this one:
 - [Advanced topics](advanced_topics.md), [declaring arguments](declaring_arguments.md)
 - [OOP notes](OOP.md), [exception handling](exceptions_handling.md)
 - [math in Lyng](math.md)
-- Some class references: [List], [Set], [Map], [Real], [Range], [Iterable], [Iterator]
+- Some class references: [List], [Set], [Map], [Real], [Range], [Iterable], [Iterator], [time manipulation](time.md)
 - Some samples: [combinatorics](samples/combinatorics.lyng.md), national vars and loops: [сумма ряда](samples/сумма_ряда.lyng.md). More at [samples folder](samples)
 
 # Expressions
@@ -668,7 +668,6 @@ are [Iterable]:
 
 Please see [Map] reference for detailed description on using Maps.
 
-
 # Flow control operators
 
 ## if-then-else
@@ -1101,6 +1100,17 @@ and you can use ranges in for-loops:
 
 See [Ranges](Range.md) for detailed documentation on it.
 
+# Time routines
+
+These should be imported from [lyng.time](time.md). For example:
+
+    import lyng.time
+
+    val now = Instant()
+    val hourAgo = now - 1.hour
+
+See [more docs on time manipulation](time.md)
+
 # Comments
 
     // single line comment

lynglib/build.gradle.kts

@@ -4,7 +4,7 @@ import org.jetbrains.kotlin.gradle.ExperimentalWasmDsl
 import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 
 group = "net.sergeych"
-version = "0.7.3-SNAPSHOT"
+version = "0.7.4-SNAPSHOT"
 
 buildscript {
     repositories {

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

@@ -42,6 +42,9 @@ data class Arguments(val list: List<Obj>,val tailBlockMode: Boolean = false) : L
         return list.map { it.toKotlin(scope) }
     }
 
+    fun inspect(): String = list.joinToString(", ") { it.inspect() }
+
+
     companion object {
         val EMPTY = Arguments(emptyList())
         fun from(values: Collection<Obj>) = Arguments(values.toList())

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

@@ -751,7 +751,7 @@ class Compiler(
         val t = cc.next()
         return when (t.type) {
             Token.Type.INT, Token.Type.HEX -> {
-                val n = t.value.toLong(if (t.type == Token.Type.HEX) 16 else 10)
+                val n = t.value.replace("_", "").toLong(if (t.type == Token.Type.HEX) 16 else 10)
                 if (isPlus) ObjInt(n) else ObjInt(-n)
             }
 

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

@@ -320,6 +320,8 @@ open class Obj {
     }
 }
 
+fun Double.toObj(): Obj = ObjReal(this)
+
 @Suppress("unused")
 inline fun <reified T> T.toObj(): Obj = Obj.from(this)
 

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

@@ -25,8 +25,7 @@ class ObjBuffer(val byteArray: UByteArray) : Obj() {
             val start: Int = index.startInt(scope)
             val end: Int = index.exclusiveIntEnd(scope) ?: size
             ObjBuffer(byteArray.sliceArray(start..<end))
-        }
-        else ObjInt(byteArray[checkIndex(scope, index)].toLong(), true)
+        } else ObjInt(byteArray[checkIndex(scope, index)].toLong(), true)
     }
 
     override suspend fun putAt(scope: Scope, index: Obj, newValue: Obj) {
@@ -42,7 +41,7 @@ class ObjBuffer(val byteArray: UByteArray) : Obj() {
     val size by byteArray::size
 
     override suspend fun compareTo(scope: Scope, other: Obj): Int {
-        if (other !is ObjBuffer) return -1
+        if (other !is ObjBuffer) return super.compareTo(scope, other)
         val limit = min(size, other.size)
         for (i in 0..<limit) {
             val own = byteArray[i]
@@ -60,7 +59,8 @@ class ObjBuffer(val byteArray: UByteArray) : Obj() {
             ObjBuffer(byteArray + other.byteArray)
         else if (other.isInstanceOf(ObjIterable)) {
             ObjBuffer(
-                byteArray + other.toFlow(scope).map { it.toLong().toUByte() }.toList().toTypedArray().toUByteArray()
+                byteArray + other.toFlow(scope).map { it.toLong().toUByte() }.toList().toTypedArray()
+                    .toUByteArray()
             )
         } else scope.raiseIllegalArgument("can't concatenate buffer with ${other.inspect()}")
     }
@@ -84,7 +84,8 @@ class ObjBuffer(val byteArray: UByteArray) : Obj() {
                 else -> {
                     if (obj.isInstanceOf(ObjIterable)) {
                         ObjBuffer(
-                            obj.toFlow(scope).map { it.toLong().toUByte() }.toList().toTypedArray().toUByteArray()
+                            obj.toFlow(scope).map { it.toLong().toUByte() }.toList().toTypedArray()
+                                .toUByteArray()
                         )
                     } else
                         scope.raiseIllegalArgument(

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

@@ -4,7 +4,7 @@ val ObjClassType by lazy { ObjClass("Class") }
 
 open class ObjClass(
     val className: String,
-    vararg val parents: ObjClass,
+    vararg parents: ObjClass,
 ) : Obj() {
 
     var instanceConstructor: Statement? = null
@@ -18,6 +18,7 @@ open class ObjClass(
 
     // members: fields most often
     private val members = mutableMapOf<String, ObjRecord>()
+    private val classMembers = mutableMapOf<String, ObjRecord>()
 
     override fun toString(): String = className
 
@@ -32,9 +33,9 @@ open class ObjClass(
         return instance
     }
 
-    fun defaultInstance(): Obj = object : Obj() {
-        override val objClass: ObjClass = this@ObjClass
-    }
+//    fun defaultInstance(): Obj = object : Obj() {
+//        override val objClass: ObjClass = this@ObjClass
+//    }
 
     fun createField(
         name: String,
@@ -49,11 +50,25 @@ open class ObjClass(
         members[name] = ObjRecord(initialValue, isMutable, visibility)
     }
 
+    fun createClassField(
+        name: String,
+        initialValue: Obj,
+        isMutable: Boolean = false,
+        visibility: Visibility = Visibility.Public,
+        pos: Pos = Pos.builtIn
+    ) {
+        val existing = classMembers[name]
+        if( existing != null)
+            throw ScriptError(pos, "$name is already defined in $objClass or one of its supertypes")
+        classMembers[name] = ObjRecord(initialValue, isMutable, visibility)
+    }
+
     fun addFn(name: String, isOpen: Boolean = false, code: suspend Scope.() -> Obj) {
         createField(name, statement { code() }, isOpen)
     }
 
     fun addConst(name: String, value: Obj) = createField(name, value, isMutable = false)
+    fun addClassConst(name: String, value: Obj) = createClassField(name, value)
 
 
     /**
@@ -68,6 +83,14 @@ open class ObjClass(
     fun getInstanceMember(atPos: Pos, name: String): ObjRecord =
         getInstanceMemberOrNull(name)
             ?: throw ScriptError(atPos, "symbol doesn't exist: $name")
+
+    override suspend fun readField(scope: Scope, name: String): ObjRecord {
+        classMembers[name]?.let {
+            println("class field $it")
+            return it
+        }
+        return super.readField(scope, name)
+    }
 }
 
 

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

@@ -0,0 +1,137 @@
+package net.sergeych.lyng
+
+import kotlin.time.Duration
+import kotlin.time.Duration.Companion.days
+import kotlin.time.Duration.Companion.hours
+import kotlin.time.Duration.Companion.milliseconds
+import kotlin.time.Duration.Companion.minutes
+import kotlin.time.Duration.Companion.seconds
+import kotlin.time.DurationUnit
+
+class ObjDuration(val duration: Duration) : Obj() {
+    override val objClass: ObjClass = type
+
+    override fun toString(): String {
+        return duration.toString()
+    }
+
+    override suspend fun compareTo(scope: Scope, other: Obj): Int {
+        return if( other is ObjDuration)
+            duration.compareTo(other.duration)
+        else -1
+    }
+
+    companion object {
+        val type = object : ObjClass("Duration") {
+            override suspend fun callOn(scope: Scope): Obj {
+                val args = scope.args
+                if( args.list.size > 1 )
+                    scope.raiseIllegalArgument("can't construct Duration(${args.inspect()})")
+                val a0 = args.list.getOrNull(0)
+
+                return ObjDuration(
+                    when (a0) {
+                        null -> Duration.ZERO
+                        is ObjInt -> a0.value.seconds
+                        is ObjReal -> a0.value.seconds
+                        else -> {
+                            scope.raiseIllegalArgument("can't construct Instant(${args.inspect()})")
+                        }
+                    }
+                )
+            }
+        }.apply {
+            addFn("days") {
+                thisAs<ObjDuration>().duration.toDouble(DurationUnit.DAYS).toObj()
+            }
+            addFn("hours") {
+                thisAs<ObjDuration>().duration.toDouble(DurationUnit.HOURS).toObj()
+            }
+            addFn("minutes") {
+                thisAs<ObjDuration>().duration.toDouble(DurationUnit.MINUTES).toObj()
+            }
+            addFn("seconds") {
+                thisAs<ObjDuration>().duration.toDouble(DurationUnit.SECONDS).toObj()
+            }
+            addFn("milliseconds") {
+                thisAs<ObjDuration>().duration.toDouble(DurationUnit.MILLISECONDS).toObj()
+            }
+            ObjInt.type.addFn("seconds") {
+                ObjDuration(thisAs<ObjInt>().value.seconds)
+            }
+
+            ObjInt.type.addFn("second") {
+                ObjDuration(thisAs<ObjInt>().value.seconds)
+            }
+
+            ObjInt.type.addFn("milliseconds") {
+                ObjDuration(thisAs<ObjInt>().value.milliseconds)
+            }
+
+            ObjInt.type.addFn("millisecond") {
+                ObjDuration(thisAs<ObjInt>().value.milliseconds)
+            }
+
+            ObjReal.type.addFn("seconds") {
+                ObjDuration(thisAs<ObjReal>().value.seconds)
+            }
+
+            ObjReal.type.addFn("second") {
+                ObjDuration(thisAs<ObjReal>().value.seconds)
+            }
+
+            ObjReal.type.addFn("milliseconds") {
+                ObjDuration(thisAs<ObjReal>().value.milliseconds)
+            }
+            ObjReal.type.addFn("millisecond") {
+                ObjDuration(thisAs<ObjReal>().value.milliseconds)
+            }
+
+            ObjInt.type.addFn("minutes") {
+                ObjDuration(thisAs<ObjInt>().value.minutes)
+            }
+            ObjReal.type.addFn("minutes") {
+                ObjDuration(thisAs<ObjReal>().value.minutes)
+            }
+            ObjInt.type.addFn("minute") {
+                ObjDuration(thisAs<ObjInt>().value.minutes)
+            }
+            ObjReal.type.addFn("minute") {
+                ObjDuration(thisAs<ObjReal>().value.minutes)
+            }
+            ObjInt.type.addFn("hours") {
+                ObjDuration(thisAs<ObjInt>().value.hours)
+            }
+            ObjReal.type.addFn("hours") {
+                ObjDuration(thisAs<ObjReal>().value.hours)
+            }
+            ObjInt.type.addFn("hour") {
+                ObjDuration(thisAs<ObjInt>().value.hours)
+            }
+            ObjReal.type.addFn("hour") {
+                ObjDuration(thisAs<ObjReal>().value.hours)
+            }
+            ObjInt.type.addFn("days") {
+                ObjDuration(thisAs<ObjInt>().value.days)
+            }
+            ObjReal.type.addFn("days") {
+                ObjDuration(thisAs<ObjReal>().value.days)
+            }
+            ObjInt.type.addFn("day") {
+                ObjDuration(thisAs<ObjInt>().value.days)
+            }
+            ObjReal.type.addFn("day") {
+                ObjDuration(thisAs<ObjReal>().value.days)
+            }
+
+
+//            addFn("epochSeconds") {
+//                val instant = thisAs<ObjInstant>().instant
+//                ObjReal(instant.epochSeconds + instant.nanosecondsOfSecond * 1e-9)
+//            }
+//            addFn("epochMilliseconds") {
+//                ObjInt(instant.toEpochMilliseconds())
+//            }
+        }
+    }
+}

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

@@ -0,0 +1,91 @@
+package net.sergeych.lyng
+
+import kotlinx.datetime.Clock
+import kotlinx.datetime.Instant
+import kotlinx.datetime.isDistantFuture
+import kotlinx.datetime.isDistantPast
+
+class ObjInstant(val instant: Instant) : Obj() {
+    override val objClass: ObjClass get() = type
+
+    override fun toString(): String {
+        return instant.toString()
+    }
+
+    override suspend fun plus(scope: Scope, other: Obj): Obj {
+        return when (other) {
+            is ObjDuration -> ObjInstant(instant + other.duration)
+            else -> super.plus(scope, other)
+        }
+    }
+
+    override suspend fun minus(scope: Scope, other: Obj): Obj {
+        return when (other) {
+            is ObjDuration -> ObjInstant(instant - other.duration)
+            is ObjInstant -> ObjDuration(instant - other.instant)
+            else -> super.plus(scope, other)
+        }
+    }
+
+    override suspend fun compareTo(scope: Scope, other: Obj): Int {
+        if( other is ObjInstant) {
+            return instant.compareTo(other.instant)
+        }
+        return super.compareTo(scope, other)
+    }
+
+    companion object {
+        val distantFuture by lazy {
+            ObjInstant(Instant.DISTANT_FUTURE)
+        }
+
+        val distantPast by lazy {
+            ObjInstant(Instant.DISTANT_PAST)
+        }
+
+        val type = object : ObjClass("Instant") {
+            override suspend fun callOn(scope: Scope): Obj {
+                val args = scope.args
+                val a0 = args.list.getOrNull(0)
+                return ObjInstant(
+                    when (a0) {
+                        null -> {
+                            val t = Clock.System.now()
+                            Instant.fromEpochSeconds(t.epochSeconds, (t.nanosecondsOfSecond / 1_000_000).toLong()*1_000_000)
+                        }
+                        is ObjInt -> Instant.fromEpochSeconds(a0.value)
+                        is ObjReal -> {
+                            val seconds = a0.value.toLong()
+                            val nanos = (a0.value - seconds) * 1e9
+                            Instant.fromEpochSeconds(seconds, nanos.toLong())
+                        }
+                        is ObjInstant -> a0.instant
+
+                        else -> {
+                            scope.raiseIllegalArgument("can't construct Instant(${args.inspect()})")
+                        }
+                    }
+                )
+            }
+        }.apply {
+            addFn("epochSeconds") {
+                val instant = thisAs<ObjInstant>().instant
+                ObjReal(instant.epochSeconds + instant.nanosecondsOfSecond * 1e-9)
+            }
+            addFn("isDistantFuture") {
+                thisAs<ObjInstant>().instant.isDistantFuture.toObj()
+            }
+            addFn("isDistantPast") {
+                thisAs<ObjInstant>().instant.isDistantPast.toObj()
+            }
+            addClassConst("distantFuture", distantFuture)
+            addClassConst("distantPast", distantPast)
+//            addFn("epochMilliseconds") {
+//                ObjInt(instant.toEpochMilliseconds())
+//            }
+        }
+
+    }
+}
+
+

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

@@ -250,7 +250,7 @@ private class Parser(fromPos: Pos) {
 
             in digitsSet -> {
                 pos.back()
-                decodeNumber(loadChars(digits), from)
+                decodeNumber(loadChars { it in digitsSet || it == '_'}, from)
             }
 
             '\'' -> {

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

@@ -179,6 +179,20 @@ class Script(
                 addPackage("lyng.buffer") {
                     it.addConst("Buffer", ObjBuffer.type)
                 }
+                addPackage("lyng.time") {
+                    it.addConst("Instant", ObjInstant.type)
+                    it.addConst("Duration", ObjDuration.type)
+                    it.addFn("delay") {
+                        val a = args.firstAndOnly()
+                        when(a) {
+                            is ObjInt -> delay(a.value * 1000)
+                            is ObjReal -> delay((a.value * 1000).roundToLong())
+                            is ObjDuration -> delay(a.duration)
+                            else -> raiseIllegalArgument("Expected Duration, Int or Real, got ${a.inspect()}")
+                        }
+                        ObjVoid
+                    }
+                }
             }
 
         }

lynglib/src/commonTest/kotlin/ScriptTest.kt

@@ -1,3 +1,4 @@
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.toList
 import kotlinx.coroutines.test.runTest
@@ -2513,4 +2514,50 @@ class ScriptTest {
         """.trimIndent())
     }
 
+    @Test
+    fun testInstant() = runTest {
+        eval(
+            """
+            import lyng.time
+            
+            val now = Instant()
+//            assertEquals( now.epochSeconds, Instant(now.epochSeconds).epochSeconds )
+
+            assert( 10.seconds is Duration )
+            assertEquals( 10.seconds, Duration(10) )
+            assertEquals( 10.milliseconds, Duration(0.01) )
+            assertEquals( 10.milliseconds, 0.01.seconds )
+            assertEquals( 1001.5.milliseconds, 1.0015.seconds )
+
+            val n1 = now + 7.seconds
+            assert( n1 is Instant )
+
+            assertEquals( n1 - now, 7.seconds )
+            assertEquals( now - n1, -7.seconds )
+            
+            """.trimIndent()
+        )
+        delay(1000)
+    }
+    @Test
+    fun testTimeStatics() = runTest {
+        eval(
+            """
+            import lyng.time
+            assert( 100.minutes is Duration )
+            assert( 100.days is Duration )
+            assert( 1.day == 24.hours )
+            assert( 1.day.hours == 24 )
+            assert( 1.hour.seconds == 3600 )
+            assert( 1.minute.milliseconds == 60_000 )
+            
+            assert(Instant.distantFuture is Instant)
+            assert(Instant.distantPast is Instant)
+            assert( Instant.distantFuture - Instant.distantPast > 70_000_000.days)
+            val maxRange = Instant.distantFuture - Instant.distantPast
+            println("всего лет %g"(maxRange.days/365.2425))
+            """.trimIndent()
+        )
+    }
+
 }

lynglib/src/jvmTest/kotlin/BookTest.kt

@@ -2,6 +2,7 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.flow
 import kotlinx.coroutines.flow.flowOn
+import kotlinx.coroutines.runBlocking
 import kotlinx.coroutines.test.runTest
 import net.sergeych.lyng.ObjVoid
 import net.sergeych.lyng.Scope
@@ -105,6 +106,10 @@ fun parseDocTests(fileName: String, bookMode: Boolean = false): Flow<DocTest> =
                         } else {
                             var isValid = true
                             val result = mutableListOf<String>()
+
+                            // remove empty trails:
+                            while( block.last().isEmpty() ) block.removeLast()
+
                             while (block.size > outStart) {
                                 val line = block.removeAt(outStart)
                                 if (!line.startsWith(">>> ")) {
@@ -288,4 +293,10 @@ class BookTest {
     fun testExceptionsBooks() = runTest {
         runDocTests("../docs/exceptions_handling.md")
     }
+
+    @Test
+    fun testTimeBooks() = runBlocking {
+        runDocTests("../docs/time.md")
+    }
+
 }