fix functions

docs/source/programming.rst

@@ -267,23 +267,34 @@ You can also create loops by using the ``goto`` statement, but this should be av
 Conditional Execution
 ---------------------
 
-@todo
-
-Conditional execution means that the flow of execution changes based on certiain conditions,
-rather than having fixed gotos or subroutine calls. IL65 has a *conditional goto* statement for this,
-that is translated into a comparison (if needed) and then a conditional branch instruction::
-
-	if[_XX] [<expression>] goto <label>
-
-
-The if-status XX is one of: [cc, cs, vc, vs, eq, ne, true, not, zero, pos, neg, lt, gt, le, ge]
+.. todo::
+	not sure how to handle direct translation into
+	[cc, cs, vc, vs, eq, ne, true, not, zero, pos, neg, lt, gt, le, ge]
 	It defaults to 'true' (=='ne', not-zero) if omitted. ('pos' will translate into 'pl', 'neg' into 'mi')
 	@todo signed: lts==neg?, gts==eq+pos?, les==neg+eq?, ges==pos?
 
-The <expression> is optional. If it is provided, it will be evaluated first. Only the [true] and [not] and [zero]
-if-statuses can be used when such a *comparison expression* is used. An example is::
+.. todo::
+	eventually allow local variable definitions inside the sub blocks but for now,
+	they have to use the same variables as the block the ``if`` statement itself is in.
+
+
+Conditional execution means that the flow of execution changes based on certiain conditions,
+rather than having fixed gotos or subroutine calls::
+
+	if A > 4 goto overflow
+
+	if X == 3 then Y = 4
+	if X == 3 then Y = 4 else A = 2
+
+	if X == 5 {
+		Y = 99
+	} else {
+		A = 3
+	}
+
+condition = arithmetic expression or  logical expression or  comparison expression or  status_register_flags ( ``SR.cs`` , ``SR.cc``, ``SR.pl`` etc... @todo )
+
 
-        if_not  A > 55  goto  more_iterations
 
 
 Conditional jumps are compiled into 6502's branching instructions (such as ``bne`` and ``bcc``) so

docs/source/syntaxreference.rst

@@ -467,8 +467,15 @@ conditional execution
 
 @todo::
 
-	if  <condition>   <single_statement or subblock>
-	  [else   <single_statement or subblock>]
+	if  <condition>  goto  <location>
+	if  <condition>  then  <simple_stateument>  [else  <simple_statement> ]
+
+	if  <condition>  {
+		<statements>
+	}
+	[ else {
+	  	<alternative statements>
+	} ]
 
 	condition = arithmetic expression
 		or  logical expression

il65/antlr/il65.g4

@@ -62,6 +62,7 @@ statement :
 	| augassignment
 	| unconditionaljump
 	| postincrdecr
+	| functioncall_stmt
 	| subroutine
 	| inlineasm
 	| labeldef
@@ -138,6 +139,12 @@ functioncall :
 	(identifier | scoped_identifier) '(' expression_list? ')'
 	;
 
+
+functioncall_stmt :
+	(identifier | scoped_identifier) '(' expression_list? ')'
+	;
+
+
 expression_list :
 	expression (',' expression)*
 	;

il65/examples/numbergame.ill

@@ -0,0 +1,93 @@
+%output prg
+%import c64lib
+%import mathlib
+
+~ main {
+        str   name    = "?" * 80
+        str   guess   = "?" * 80
+        byte secretnumber = 0
+        byte attempts_left = 10
+        memory word freadstr_arg = $22		; argument for FREADSTR
+
+
+start:
+        c64.init_system()
+        c64.VMCSB |= 2		; lowercase charset
+
+        ; greeting
+        c64scr.print_string("Enter your name: ")
+        Y = c64scr.input_chars(name)
+        c64.CHROUT("\n")
+        c64.CHROUT("\n")
+        c64scr.print_string("Hello, ")
+        c64scr.print_string(name)
+        c64.CHROUT(".")
+        c64.CHROUT("\n")
+
+        ; create a secret random number from 1-100
+        c64.RNDA(0)             ; fac = rnd(0)
+        c64.MUL10()             ; fac *= 10
+        c64.MUL10()             ; .. and now *100
+        c64.FADDH()             ; add 0.5..
+        c64.FADDH()             ;   and again, so +1 total
+        AY = c64flt.GETADRAY()
+        secretnumber=A
+        ;A=math.randbyte()
+        ;A+=c64.RASTER
+        ;A-=c64.TIME_LO
+        ;X,secretnumber=math.divmod_bytes(A, 99)
+
+        c64scr.print_string("I am thinking of a number from 1 to 100!You'll have to guess it!\n")
+
+printloop:
+        c64scr.print_string("\nYou have ")
+        c64scr.print_byte_decimal(attempts_left)
+        c64scr.print_string(" guess")
+
+        ; @todo comparison expression so we can do if attempts_left>0 ...
+        A = attempts_left
+        A--
+        ; @todo (conditional): if_zero A goto ask_guess
+        c64scr.print_string("es")
+ask_guess:
+        c64scr.print_string(" left.\nWhat is your next guess? ")
+        Y = c64scr.input_chars(guess)
+        c64.CHROUT("\n")
+        freadstr_arg = guess
+        c64.FREADSTR(A)
+        AY = c64flt.GETADRAY()
+        A -= secretnumber       ; @todo condition so we can do if guess > secretnumber....
+        ; @todo (conditional): if_zero goto correct_guess
+        ; @todo (conditional): if_gt goto too_high
+        c64scr.print_string("That is too ")
+        c64scr.print_string("low!\n")
+        goto continue
+
+correct_guess:
+        c64scr.print_string("\nThat's my number, impressive!\n")
+        goodbye()
+        return
+
+too_high:
+        c64scr.print_string("That is too ")
+        c64scr.print_string("high!\n")
+
+continue:
+        attempts_left--
+        ; @todo (conditional): if_zero attempts_left goto game_over
+        goto printloop
+
+game_over:
+        c64scr.print_string("\nToo bad! It was: ")
+        c64scr.print_byte_decimal(secretnumber)
+        c64.CHROUT("\n")
+        return goodbye()
+        goodbye()               ; @todo fix subroutine usage tracking, it doesn't register this one
+        return
+
+sub goodbye ()->() {
+        c64scr.print_string("\nThanks for playing. Bye!\n")
+        return
+}
+
+}

il65/examples/test.ill

@@ -20,6 +20,8 @@
   XY = hopla*2+hopla1
   A = "derp" * %000100
 
+  main.foo(1,2,3)
+
 mega:
 	X=1
 cool:

il65/src/il65/Main.kt

@@ -125,7 +125,7 @@ fun main(args: Array<String>) {
         val moduleAst = loadModule(filepath)
         moduleAst.linkParents()
         val globalNamespace = moduleAst.namespace()
-        globalNamespace.debugPrint()
+        // globalNamespace.debugPrint()
 
         moduleAst.optimize(globalNamespace)
         moduleAst.checkValid(globalNamespace)      // check if final tree is valid

il65/src/il65/ast/AST.kt

@@ -81,6 +81,10 @@ interface IAstProcessor {
         functionCall.arglist = functionCall.arglist.map { it.process(this) }
         return functionCall
     }
+    fun process(functionCall: FunctionCallStatement): IStatement {
+        functionCall.arglist = functionCall.arglist.map { it.process(this) }
+        return functionCall
+    }
     fun process(identifier: Identifier): IExpression {
         return identifier
     }
@@ -102,6 +106,11 @@ interface IStatement : Node {
 }
 
 
+interface IFunctionCall {
+    var location: Identifier
+    var arglist: List<IExpression>
+}
+
 interface INameScope {
     val name: String
     val position: Position?
@@ -474,8 +483,7 @@ data class Identifier(val scopedName: List<String>) : IExpression {
             // todo add to a list of errors instead
             throw SyntaxError("name should be a constant, instead of: ${node::class.simpleName}", position)
         } else if(vardecl.type!=VarDeclType.CONST) {
-            // todo add to a list of errors instead
-            throw SyntaxError("name should be a constant, instead of: ${vardecl.type}", position)
+            return null
         }
         return vardecl.value?.constValue(namespace)
     }
@@ -513,7 +521,7 @@ data class Jump(val address: Int?, val identifier: Identifier?) : IStatement {
 }
 
 
-data class FunctionCall(var location: Identifier, var arglist: List<IExpression>) : IExpression {
+data class FunctionCall(override var location: Identifier, override var arglist: List<IExpression>) : IExpression, IFunctionCall {
     override var position: Position? = null
     override var parent: Node? = null
 
@@ -550,6 +558,20 @@ data class FunctionCall(var location: Identifier, var arglist: List<IExpression>
 }
 
 
+data class FunctionCallStatement(override var location: Identifier, override var arglist: List<IExpression>) : IStatement, IFunctionCall {
+    override var position: Position? = null
+    override var parent: Node? = null
+
+    override fun linkParents(parent: Node) {
+        this.parent = parent
+        location.linkParents(this)
+        arglist.forEach { it.linkParents(this) }
+    }
+
+    override fun process(processor: IAstProcessor) = processor.process(this)
+}
+
+
 data class InlineAssembly(val assembly: String) : IStatement {
     override var position: Position? = null
     override var parent: Node? = null
@@ -736,10 +758,39 @@ private fun il65Parser.StatementContext.toAst(withPosition: Boolean) : IStatemen
     val asm = inlineasm()?.toAst(withPosition)
     if(asm!=null) return asm
 
+    val fcall = functioncall_stmt()?.toAst(withPosition)
+    if(fcall!=null) return fcall
+
     throw UnsupportedOperationException(text)
 }
 
 
+private fun il65Parser.Functioncall_stmtContext.toAst(withPosition: Boolean): IStatement {
+    val location =
+            if(identifier()!=null) identifier()?.toAst(withPosition)
+            else scoped_identifier()?.toAst(withPosition)
+    val fcall = if(expression_list()==null)
+        FunctionCallStatement(location!!, emptyList())
+    else
+        FunctionCallStatement(location!!, expression_list().toAst(withPosition))
+    fcall.position = toPosition(withPosition)
+    return fcall
+}
+
+
+private fun il65Parser.FunctioncallContext.toAst(withPosition: Boolean): FunctionCall {
+    val location =
+            if(identifier()!=null) identifier()?.toAst(withPosition)
+            else scoped_identifier()?.toAst(withPosition)
+    val fcall = if(expression_list()==null)
+        FunctionCall(location!!, emptyList())
+    else
+        FunctionCall(location!!, expression_list().toAst(withPosition))
+    fcall.position = toPosition(withPosition)
+    return fcall
+}
+
+
 private fun il65Parser.InlineasmContext.toAst(withPosition: Boolean): IStatement {
     val asm = InlineAssembly(INLINEASMBLOCK().text)
     asm.position = toPosition(withPosition)
@@ -892,16 +943,8 @@ private fun il65Parser.ExpressionContext.toAst(withPosition: Boolean) : IExpress
         return expr
     }
 
-    val funcall = functioncall()
-    if(funcall!=null) {
-        val location = funcall.identifier().toAst(withPosition)
-        val fcall = if(funcall.expression_list()==null)
-            FunctionCall(location, emptyList())
-        else
-            FunctionCall(location, funcall.expression_list().toAst(withPosition))
-        fcall.position = funcall.toPosition(withPosition)
-        return fcall
-    }
+    val funcall = functioncall()?.toAst(withPosition)
+    if(funcall!=null) return funcall
 
     if (rangefrom!=null && rangeto!=null) {
         val rexp = RangeExpr(rangefrom.toAst(withPosition), rangeto.toAst(withPosition))

il65/src/il65/ast/AstChecker.kt

@@ -167,7 +167,8 @@ class AstChecker(private val globalNamespace: INameScope) : IAstProcessor {
             }
             VarDeclType.MEMORY -> {
                 if(decl.value !is LiteralValue)
-                    throw AstException("${decl.value?.position} value of memory var decl is not a literal (it is a ${decl.value!!::class.simpleName}). This is likely a bug in the AstOptimizer")
+                    // @todo normal error reporting
+                    throw AstException("${decl.value?.position} value of memory var decl is not a literal (it is a ${decl.value!!::class.simpleName}).")
 
                 val value = decl.value as LiteralValue
                 if(value.intvalue==null || value.intvalue<0 || value.intvalue>65535) {