fixed comment before else in if;

dynamic now support indexing access

docs/OOP.md

@@ -266,7 +266,7 @@ The same we can provide writable dynamic fields (var-type), adding set method:
                 // constant field
                 "foo" -> "bar"
                 // mutable field
-                "bar" -> setValueForBar 
+                "bar" -> storedValueForBar 
 
                 else -> throw SymbolNotFoundException()
             }
@@ -289,9 +289,56 @@ The same we can provide writable dynamic fields (var-type), adding set method:
     assertThrows {
         accessor.bad = "!23"
     }
+    void
+    >>> void
 
 Of course, you can return any object from dynamic fields; returning lambdas let create _dynamic methods_ - the callable method. It is very convenient to implement libraries with dynamic remote interfaces, etc.
 
+### Dynamic indexers
+
+Index access for dynamics is passed to the same getter and setter, so it is
+generally the same:
+
+    var storedValue = "bar"
+    val x = dynamic {
+        get { 
+            if( it == "foo" ) storedValue
+            else null
+        }
+    }
+    assertEquals("bar", x["foo"] )
+    assertEquals("bar", x.foo )
+    >>> void
+
+And assigning them works the same. You can make it working
+mimicking arrays, but remember, it is not Collection so
+collection's sugar won't work with it:
+
+    var storedValue = "bar"
+    val x = dynamic {
+        get { 
+            when(it) {
+                "size" -> 1
+                0 -> storedValue
+                else -> null
+            }
+        }
+        set { index, value -> 
+            if( index == 0 ) storedValue = value
+            else throw "Illegal index: "+index
+        }
+    }
+    assertEquals("bar", x[0] )
+    assertEquals(1, x.size )
+    x[0] = "buzz"
+    assertThrows { x[1] = 1 }
+    assertEquals("buzz", storedValue)
+    assertEquals("buzz", x[0])
+    >>> void
+
+If you want dynamic to function like an array, create a [feature
+request](https://gitea.sergeych.net/SergeychWorks/lyng/issues).
+
 # Theory
 
 ## Basic principles:

gradle/libs.versions.toml

@@ -4,7 +4,7 @@ clikt = "5.0.3"
 kotlin = "2.2.20"
 android-minSdk = "24"
 android-compileSdk = "34"
-kotlinx-coroutines = "1.9.0"
+kotlinx-coroutines = "1.10.2"
 mp_bintools = "0.1.12"
 firebaseCrashlyticsBuildtools = "3.0.3"
 okioVersion = "3.10.2"

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

@@ -888,6 +888,7 @@ class Compiler(
         }
     }
 
+    @Suppress("SameParameterValue")
     private fun parseNumber(isPlus: Boolean): Obj {
         return parseNumberOrNull(isPlus) ?: throw ScriptError(cc.currentPos(), "Expecting number")
     }
@@ -1681,7 +1682,7 @@ class Compiler(
 
         cc.skipTokenOfType(Token.Type.NEWLINE, isOptional = true)
         // could be else block:
-        val t2 = cc.next()
+        val t2 = cc.nextNonWhitespace()
 
         // we generate different statements: optimization
         return if (t2.type == Token.Type.ID && t2.value == "else") {

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

@@ -28,7 +28,9 @@ data class Pos(val source: Source, val line: Int, val column: Int) {
         else if( line > 0) Pos(source, line-1, source.lines[line-1].length - 1)
         else throw IllegalStateException("can't go back from line 0, column 0")
 
-    val currentLine: String get() = if( end ) "EOF" else source.lines[line]
+    val currentLine: String get() =
+        if( end ) "EOF"
+        else if( line >= 0 ) source.lines[line] else "<no line information>"
 
     val end: Boolean get() = line >= source.lines.size
 

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

@@ -26,7 +26,7 @@ open class ScriptError(val pos: Pos, val errorMessage: String, cause: Throwable?
         $pos: Error: $errorMessage
         
         ${pos.currentLine}
-        ${"-".repeat(pos.column)}^
+        ${if( pos.column >= 0 ) "-".repeat(pos.column) + "^" else ""}
     """.trimIndent(),
     cause
 )

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

@@ -67,6 +67,16 @@ class ObjDynamic : Obj() {
             ?: super.writeField(scope, name, newValue)
     }
 
+    override suspend fun getAt(scope: Scope, index: Obj): Obj {
+        return readCallback?.execute( scope.copy(Arguments(index)))
+            ?: super.getAt(scope, index)
+    }
+
+    override suspend fun putAt(scope: Scope, index: Obj, newValue: Obj) {
+        writeCallback?.execute(scope.copy(Arguments(index, newValue)))
+            ?: super.putAt(scope, index, newValue)
+    }
+
     companion object {
 
         suspend fun create(scope: Scope, builder: Statement): ObjDynamic {
@@ -76,7 +86,9 @@ class ObjDynamic : Obj() {
             return delegate
         }
 
-        val type = object : ObjClass("Delegate") {}
+        val type = object : ObjClass("Delegate") {}.apply {
+//            addClassConst("IndexGetName", operatorGetName)
+        }
     }
 
 }

lynglib/src/commonTest/kotlin/OOTest.kt

@@ -107,6 +107,26 @@ class OOTest {
         """.trimIndent())
     }
 
+    @Test
+    fun testDynamicIndexAccess() = runTest {
+        eval("""
+            val store = Map()
+            val accessor = dynamic {
+                get { name ->
+                    store[name]
+                }
+                set { name, value ->
+                    store[name] = value
+                }
+            }
+           assertEquals(null, accessor["foo"])
+           assertEquals(null, accessor.foo)
+           accessor["foo"] = "bar"
+           assertEquals("bar", accessor["foo"])
+           assertEquals("bar", accessor.foo)
+        """.trimIndent())
+    }
+
     @Test
     fun testMultilineConstructor() = runTest {
         eval("""