+better comparison

+splat arguments in calls

docs/List.md

@@ -39,6 +39,7 @@ __Important__ negative indexes works wherever indexes are used, e.g. in insertio
     assert( [1, 2, 3] > [1, 2])
     assert( [1, 3] > [1, 2, 3])
     assert( [1, 2, 3] == [1, 2, 3])
+    assert( [1, 2, 3] != [1, 2, "three"])
     // note that in the case above objects are referentially different:
     assert( [1, 2, 3] !== [1, 2, 3])
     >>> void

docs/tutorial.md

@@ -342,6 +342,27 @@ You can insert elements at any position using `addAt`:
     assert( x == [1, "foo", "bar", 2, 3])
     >>> void
 
+Using splat arguments can simplify inserting list in list:
+
+    val x = [1, 2, 3]
+    x.addAt( 1, ...[0,100,0])
+    x
+    >>> [1, 0, 100, 0, 2, 3]
+
+Using negative indexes can insert elements as offset from the end, for example:
+    
+    val x = [1,2,3]
+    x.addAt(-1, 10)
+    x
+    >>> [1, 2, 10, 3]
+
+Note that to add to the end you still need to use `add` or positive index of the after-last element:
+
+    val x = [1,2,3]
+    x.addAt(3, 10)
+    x
+    >>> [1, 2, 3, 10]
+
 ## Removing list items
 
     val x = [1, 2, 3, 4, 5]
@@ -352,6 +373,21 @@ You can insert elements at any position using `addAt`:
     assert( x == [1, 5])
     >>> void
 
+Again, you can use negative indexes. For example, removing last elements like:
+
+    val x = [1, 2, 3, 4, 5]
+
+    // remove last:
+    x.removeAt(-1)
+    assert( x == [1, 2, 3, 4])
+    
+    // remove 3 last:
+    x.removeAt(-3,1)    
+    assert( x == [1])
+    >>> void
+    
+
+
 # Flow control operators
 
 ## if-then-else

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

@@ -1,15 +1,31 @@
 package net.sergeych.ling
 
-data class Arguments(val list: List<Info>): Iterable<Obj> {
+data class ParsedArgument(val value: Statement, val pos: Pos, val isSplat: Boolean = false)
 
-    data class Info(val value: Obj,val pos: Pos)
+suspend fun Collection<ParsedArgument>.toArguments(context: Context): Arguments {
+    val list = mutableListOf<Arguments.Info>()
+
+    for (x in this) {
+        val value = x.value.execute(context)
+        if (x.isSplat) {
+            (value as? ObjList) ?: context.raiseClassCastError("expected list of objects for splat argument")
+            for (subitem in value.list) list.add(Arguments.Info(subitem, x.pos))
+        } else
+            list.add(Arguments.Info(value, x.pos))
+    }
+    return Arguments(list)
+}
+
+data class Arguments(val list: List<Info>) : Iterable<Obj> {
+
+    data class Info(val value: Obj, val pos: Pos)
 
     val size by list::size
 
     operator fun get(index: Int): Obj = list[index].value
 
     fun firstAndOnly(): Obj {
-        if( list.size != 1 ) throw IllegalArgumentException("Expected one argument, got ${list.size}")
+        if (list.size != 1) throw IllegalArgumentException("Expected one argument, got ${list.size}")
         return list.first().value
     }
 
@@ -20,4 +36,6 @@ data class Arguments(val list: List<Info>): Iterable<Obj> {
     override fun iterator(): Iterator<Obj> {
         return list.map { it.value }.iterator()
     }
+
 }
+

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

@@ -148,10 +148,7 @@ class Compiler(
                                         v.callInstanceMethod(
                                             context,
                                             next.value,
-                                            Arguments(args.map {
-                                                val st = it.value as Statement
-                                                Arguments.Info(st.execute(context),it.pos) }
-                                            )
+                                            args.toArguments(context)
                                         ), isMutable = false
                                     )
                                 }
@@ -275,11 +272,11 @@ class Compiler(
                     } ?: run {
                         // no lvalue means pre-increment, expression to increment follows
                         val next = parseAccessor(cc) ?: throw ScriptError(t.pos, "Expecting expression")
-                        operand = Accessor({ ctx ->
+                        operand = Accessor { ctx ->
                             next.getter(ctx).also {
                                 if (!it.isMutable) ctx.raiseError("Cannot increment immutable value")
                             }.value.incrementAndGet(ctx).asReadonly
-                        })
+                        }
                     }
                 }
 
@@ -351,15 +348,19 @@ class Compiler(
         }
     }
 
-    private fun parseArgs(cc: CompilerContext): List<Arguments.Info> {
-        val args = mutableListOf<Arguments.Info>()
+    private fun parseArgs(cc: CompilerContext): List<ParsedArgument> {
+        val args = mutableListOf<ParsedArgument>()
         do {
             val t = cc.next()
             when (t.type) {
                 Token.Type.RPAREN, Token.Type.COMMA -> {}
+                Token.Type.ELLIPSIS -> {
+                    parseStatement(cc)?.let { args += ParsedArgument(it, t.pos, isSplat = true) }
+                        ?: throw ScriptError(t.pos, "Expecting arguments list")
+                }
                 else -> {
                     cc.previous()
-                    parseStatement(cc)?.let { args += Arguments.Info(it, t.pos) }
+                    parseStatement(cc)?.let { args += ParsedArgument(it, t.pos) }
                         ?: throw ScriptError(t.pos, "Expecting arguments list")
                 }
             }
@@ -376,9 +377,10 @@ class Compiler(
             val v = left.getter(context)
             v.value.callOn(context.copy(
                 context.pos,
-                Arguments(
-                    args.map { Arguments.Info((it.value as Statement).execute(context), it.pos) }
-                ),
+                args.toArguments(context)
+//                Arguments(
+//                    args.map { Arguments.Info((it.value as Statement).execute(context), it.pos) }
+//                ),
             )
             ).asReadonly
         }

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

@@ -55,11 +55,6 @@ sealed class Obj {
             ?: throw ScriptError(atPos, "symbol doesn't exist: $name")
 
     suspend fun callInstanceMethod(context: Context, name: String, args: Arguments): Obj =
-    // instance _methods_ are our ObjClass instance:
-    // note that getInstanceMember traverses the hierarchy
-    // instance _methods_ are our ObjClass instance:
-    // note that getInstanceMember traverses the hierarchy
-// instance _methods_ are our ObjClass instance:
         // note that getInstanceMember traverses the hierarchy
         objClass.getInstanceMember(context.pos, name).value.invoke(context, this, args)
 
@@ -154,7 +149,7 @@ sealed class Obj {
         // could be property or class field:
         val obj = objClass.getInstanceMemberOrNull(name)
         val value = obj?.value
-        return when(value) {
+        return when (value) {
             is Statement -> {
                 // readonly property, important: call it on this
                 value.execute(context.copy(context.pos, newThisObj = this)).asReadonly
@@ -253,7 +248,7 @@ object ObjNull : Obj() {
 data class ObjString(val value: String) : Obj() {
 
     override suspend fun compareTo(context: Context, other: Obj): Int {
-        if (other !is ObjString) context.raiseError("cannot compare string with $other")
+        if (other !is ObjString) return -2
         return this.value.compareTo(other.value)
     }
 
@@ -311,7 +306,7 @@ data class ObjReal(val value: Double) : Obj(), Numeric {
     override fun byValueCopy(): Obj = ObjReal(value)
 
     override suspend fun compareTo(context: Context, other: Obj): Int {
-        if (other !is Numeric) context.raiseError("cannot compare $this with $other")
+        if (other !is Numeric) return -2
         return value.compareTo(other.doubleValue)
     }
 
@@ -372,7 +367,7 @@ data class ObjInt(var value: Long) : Obj(), Numeric {
     }
 
     override suspend fun compareTo(context: Context, other: Obj): Int {
-        if (other !is Numeric) context.raiseError("cannot compare $this with $other")
+        if (other !is Numeric) return -2
         return value.compareTo(other.doubleValue)
     }
 
@@ -412,7 +407,7 @@ data class ObjInt(var value: Long) : Obj(), Numeric {
      * assignment
      */
     override suspend fun assign(context: Context, other: Obj): Obj? {
-        return if( other is ObjInt) {
+        return if (other is ObjInt) {
             value = other.value
             this
         } else null
@@ -427,7 +422,7 @@ data class ObjBool(val value: Boolean) : Obj() {
     override val asStr by lazy { ObjString(value.toString()) }
 
     override suspend fun compareTo(context: Context, other: Obj): Int {
-        if (other !is ObjBool) context.raiseError("cannot compare $this with $other")
+        if (other !is ObjBool) return -2
         return value.compareTo(other.value)
     }
 

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

@@ -6,8 +6,9 @@ class ObjList(val list: MutableList<Obj>) : Obj() {
         list.joinToString(separator = ", ") { it.inspect() }
     }]"
 
-    fun normalize(context: Context, index: Int): Int {
+    fun normalize(context: Context, index: Int,allowInclusiveEnd: Boolean = false): Int {
         val i = if (index < 0) list.size + index else index
+        if( allowInclusiveEnd && i == list.size ) return i
         if (i !in list.indices) context.raiseError("index $index out of bounds for size ${list.size}")
         return i
     }
@@ -23,7 +24,7 @@ class ObjList(val list: MutableList<Obj>) : Obj() {
     }
 
     override suspend fun compareTo(context: Context, other: Obj): Int {
-        if (other !is ObjList) context.raiseError("cannot compare $this with $other")
+        if (other !is ObjList) return -2
         val mySize = list.size
         val otherSize = other.list.size
         val commonSize = minOf(mySize, otherSize)
@@ -72,7 +73,8 @@ class ObjList(val list: MutableList<Obj>) : Obj() {
                 statement {
                     if (args.size < 2) raiseError("addAt takes 2+ arguments")
                     val l = thisAs<ObjList>()
-                    var index = l.normalize(this, requiredArg<ObjInt>(0).value.toInt())
+                    var index = l.normalize(this, requiredArg<ObjInt>(0).value.toInt(),
+                        allowInclusiveEnd = true)
                     for (i in 1..<args.size) l.list.add(index++, args[i])
                     ObjVoid
                 }