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fixed doRepeat blocks to push copied versions onto the stack

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- need to copy so that when the repeat block is in a procedure
  and within the repeat that procedure is called, a separate
  repeat is pushed onto the stack and counted down
This commit is contained in:
Chad Walker 2014-09-17 22:45:54 -05:00
parent 64850c14a6
commit 4e489c258d
1 changed files with 10 additions and 3 deletions
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13
js/Interpreter.js
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@ -26,7 +26,7 @@ var Block = function(opAndArgs, optionalSubstack) {
this.args = opAndArgs.slice(1); // arguments can be either or constants (numbers, boolean strings, etc.) or expressions (Blocks)
this.isLoop = false; // set to true for loop blocks the first time they run
this.substack = optionalSubstack;
this.subStack2 = null;
this.substack2 = null;
this.nextBlock = null;
this.tmp = -1;
// used in procedure blocks and call blocks
@ -39,7 +39,7 @@ var Block = function(opAndArgs, optionalSubstack) {
Block.copyBlock = function (srcBlock) {
var dstBlock = new Block([srcBlock.op]);
['primFcn', 'args', 'isLoop', 'substack', 'subStack2', 'nextBlock', 'tmp', 'namedParams', 'asyncFlag'].forEach(function (property) {
['primFcn', 'args', 'isLoop', 'substack', 'substack2', 'nextBlock', 'tmp', 'namedParams', 'asyncFlag'].forEach(function (property) {
dstBlock[property] = srcBlock[property];
});
return dstBlock;
@ -166,6 +166,7 @@ Interpreter.prototype.stepActiveThread = function() {
}
b.primFcn(b);
if (this.yield) { this.activeThread.nextBlock = b; return; }
b = this.activeThread.nextBlock; // refresh local variable b in case primitive did some control flow
while (!b) {
// end of a substack; pop the owning control flow block from stack
@ -346,6 +347,8 @@ Interpreter.prototype.primWait = function(b) {
Interpreter.prototype.primRepeat = function(b) {
if (b.tmp == -1) {
// need to copy the first time it is pushed onto the stack in startSubstack()
b = Block.copyBlock(b);
b.tmp = Math.max(interp.numarg(b, 0), 0); // Initialize repeat count on this block
}
if (b.tmp > 0) {
@ -403,6 +406,8 @@ Interpreter.prototype.startSubstack = function(b, isLoop, secondSubstack) {
// Start the substack of a control structure command such as if or forever.
b.isLoop = !!isLoop;
this.activeThread.stack.push(b); // remember the block that started the substack
//console.log('pushed', b.op, 'onto stack', interp.activeThread.stack.map(function (frame) { return frame.op; }));
if (!secondSubstack) {
this.activeThread.nextBlock = b.substack;
} else {
@ -474,8 +479,10 @@ Interpreter.prototype.primCall = function (b) {
// push the copy block onto the stack, so when the call returns we can continue
interp.activeThread.stack.push(b);
//console.log('pushed call onto stack with args:', b.procParams, interp.activeThread.stack.map(function (frame) { return frame.op; }));
// jump to the procedure
// console.log('calling procedure', procedure.args[0], b.procParams);
// need to set a noop block so that if the procedure starts with an
// console.log('running procedure.nextBlock:', procedure.nextBlock);
interp.activeThread.nextBlock = procedure.nextBlock;
};