fix some initial value datatypes and type casting in assignments

compiler/src/prog8/CompilerMain.kt

@@ -111,7 +111,7 @@ private fun compileMain(args: Array<String>) {
             }
             //println(" time2: $time2")
             val time3 = measureTimeMillis {
-                programAst.reorderStatements()     // reorder statements to please the compiler later
+                programAst.reorderStatements()     // reorder statements and add type casts, to please the compiler later
             }
             //println(" time3: $time3")
             val time4 = measureTimeMillis {

compiler/src/prog8/ast/AstChecker.kt

@@ -525,7 +525,12 @@ private class AstChecker(private val program: Program,
                     when {
                         decl.datatype in NumericDatatypes -> {
                             // initialize numeric var with value zero by default.
-                            val litVal = LiteralValue(DataType.UBYTE, 0, position = decl.position)
+                            val litVal =
+                                    when {
+                                        decl.datatype in ByteDatatypes -> LiteralValue(decl.datatype, bytevalue=0, position = decl.position)
+                                        decl.datatype in WordDatatypes -> LiteralValue(decl.datatype, wordvalue=0, position = decl.position)
+                                        else -> LiteralValue(decl.datatype, floatvalue=0.0, position = decl.position)
+                                    }
                             litVal.parent = decl
                             decl.value = litVal
                         }

compiler/src/prog8/ast/StmtReorderer.kt

@@ -22,6 +22,8 @@ private class StatementReorderer(private val program: Program): IAstProcessor {
     //
     // - the 'start' subroutine in the 'main' block will be moved to the top immediately following the directives.
     // - all other subroutines will be moved to the end of their block.
+    //
+    // Also, makes sure any value assignments get the proper type casts if needed to cast them into the target variable's type.
 
     private val directivesToMove = setOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address", "%option")
 
@@ -189,6 +191,24 @@ private class StatementReorderer(private val program: Program): IAstProcessor {
         statements.addAll(result)
     }
 
+
+    override fun process(assignment: Assignment): IStatement {
+        val target=assignment.singleTarget
+        if(target!=null) {
+            // see if a typecast is needed to convert the value's type into the proper target type
+            val valuetype = assignment.value.resultingDatatype(program)
+            val targettype = target.determineDatatype(program, assignment)
+            if(targettype!=null && valuetype!=null && valuetype!=targettype) {
+                if(valuetype isAssignableTo targettype) {
+                    assignment.value = TypecastExpression(assignment.value, targettype, assignment.value.position)
+                }
+                // if they're not assignable, we'll get a proper error later from the AstChecker
+            }
+        } else TODO("multi-target assign")
+
+        return super.process(assignment)
+    }
+
     private fun sortConstantAssignmentSequence(first: Assignment, stmtIter: MutableIterator<IStatement>): Pair<List<Assignment>, IStatement?> {
         val sequence= mutableListOf(first)
         var trailing: IStatement? = null

compiler/src/prog8/astvm/AstVm.kt

@@ -198,7 +198,25 @@ class AstVm(val program: Program) {
                 } else TODO("$stmt")
             }
             is PostIncrDecr -> {
-                TODO("$stmt")
+                when {
+                    stmt.target.identifier!=null -> {
+                        val ident = stmt.definingScope().lookup(stmt.target.identifier!!.nameInSource, stmt) as VarDecl
+                        val identScope = ident.definingScope()
+                        var value = runtimeVariables.get(identScope, ident.name)
+                        value = when {
+                            stmt.operator=="++" -> value.add(RuntimeValue(value.type, 1))
+                            stmt.operator=="--" -> value.sub(RuntimeValue(value.type, 1))
+                            else -> throw VmExecutionException("strange postincdec operator $stmt")
+                        }
+                        runtimeVariables.set(identScope, ident.name, value)
+                    }
+                    stmt.target.memoryAddress!=null -> {
+                        TODO("$stmt")
+                    }
+                    stmt.target.arrayindexed!=null -> {
+                        TODO("$stmt")
+                    }
+                }
             }
             is Jump -> {
                 TODO("$stmt")

examples/primes.p8

@@ -37,11 +37,12 @@
 
         ; found next one, mark the multiples and return it.
         sieve[candidate_prime] = true
-        ; uword multiple = candidate_prime        ; TODO the parser should have added a type cast from UBYTE to UWORD here
-        uword multiple = candidate_prime as uword        ; TODO should not be required
+        uword multiple = candidate_prime
+
+
         while multiple < len(sieve) {
             sieve[lsb(multiple)] = true
-            multiple += candidate_prime as uword   ; TODO cast should not be required
+            multiple += candidate_prime
             c64scr.print_uw(multiple)       ; TODO
             c64.CHROUT('\n')        ; TODO
         }

examples/test.p8

@@ -4,58 +4,17 @@
 
     sub start() {
 
-        greeting()
-
-        ubyte square = stuff.function(12)
-
-        c64scr.print_ub(square)
-        c64.CHROUT('\n')
-
-        stuff.name()
-        stuff.name()
-        stuff.bye()
-
-        abs(4)
-        abs(4)
-        abs(4)
-        abs(4)
-        abs(4)
-        foobar()
-        foobar()
-        foobar()
-        foobar()
-
-
-        if(false) {
-        } else {
+        uword multiple
 
+        while multiple < 5 {
+            multiple += 2
+            c64scr.print_uw(multiple)       ; TODO
+            c64.CHROUT('\n')        ; TODO
         }
 
+        c64scr.print("done!\n")
 
     }
 
 
-    sub foobar() {
-    }
-
-    sub greeting() {
-        c64scr.print("hello\n")
-    }
-}
-
-
-~ stuff {
-
-    sub function(ubyte v) -> ubyte {
-        return v*v
-    }
-
-    sub name() {
-        c64scr.print("name\n")
-    }
-
-    sub bye() {
-        c64scr.print("bye\n")
-    }
-
 }