Prototype implementation of yielding reporters

This commit is contained in:
Tim Mickel 2016-06-17 15:10:12 -04:00
parent 34659c9b7b
commit 97f7571c6f
3 changed files with 61 additions and 12 deletions

View file

@ -1,10 +1,19 @@
var Thread = require('./thread');
/**
* If set, block calls, args, and return values will be logged to the console.
* @const {boolean}
*/
var DEBUG_BLOCK_CALLS = true;
var execute = function (sequencer, thread) {
/**
* Execute a block.
* @param {!Sequencer} sequencer Which sequencer is executing.
* @param {!Thread} thread Thread which to read and execute.
* @param {string=} opt_waitingInputName If evaluating an input, its name.
* @return {?Any} Reported value, if available immediately.
*/
var execute = function (sequencer, thread, opt_waitingInputName) {
var runtime = sequencer.runtime;
// Current block to execute is the one on the top of the stack.
@ -27,11 +36,29 @@ var execute = function (sequencer, thread) {
for (var inputName in inputs) {
var input = inputs[inputName];
var inputBlockId = input.block;
// Push to the stack to evaluate this input.
thread.pushStack(inputBlockId);
var result = execute(sequencer, thread);
thread.popStack();
argValues[input.name] = result;
// Is there a value for this input waiting in the stack frame?
if (currentStackFrame.reported &&
currentStackFrame.reported[inputName]) {
// Use that value.
argValues[inputName] = currentStackFrame.reported[inputName];
} else {
// Otherwise, we need to evaluate the block.
// Push to the stack to evaluate this input.
thread.pushStack(inputBlockId);
if (DEBUG_BLOCK_CALLS) {
console.time('Yielding reporter evaluation');
}
var result = execute(sequencer, thread, inputName);
// Did the reporter yield?
if (thread.status === Thread.STATUS_YIELD) {
// Reporter yielded; don't pop stack and wait for it to unyield.
// The value will be populated once the reporter unyields,
// and passed up to the currentStackFrame on next execution.
return;
}
thread.popStack();
argValues[inputName] = result;
}
}
if (!opcode) {
@ -51,21 +78,29 @@ var execute = function (sequencer, thread) {
console.log('and stack frame: ', currentStackFrame);
}
var primitiveReturnValue = null;
// @todo deal with the return value
primitiveReturnValue = blockFunction(argValues, {
yield: thread.yield.bind(thread),
done: function() {
sequencer.proceedThread(thread);
},
report: function(reportedValue) {
thread.pushReportedValue(opt_waitingInputName, reportedValue);
if (DEBUG_BLOCK_CALLS) {
console.log('Reported: ', reportedValue,
' for ', opt_waitingInputName);
console.timeEnd('Yielding reporter evaluation');
}
sequencer.proceedThread(thread);
},
timeout: thread.addTimeout.bind(thread),
stackFrame: currentStackFrame,
stackFrame: currentStackFrame.executionContext,
startSubstack: function (substackNum) {
sequencer.stepToSubstack(thread, substackNum);
}
});
if (DEBUG_BLOCK_CALLS) {
console.log('ending stack frame: ', currentStackFrame);
console.log('returned: ', primitiveReturnValue);
console.log('returned immediately: ', primitiveReturnValue);
console.groupEnd();
}
return primitiveReturnValue;

View file

@ -1,6 +1,5 @@
var Timer = require('../util/timer');
var Thread = require('./thread');
var YieldTimers = require('../util/yieldtimers.js');
var execute = require('./execute.js');
function Sequencer (runtime) {
@ -101,7 +100,7 @@ Sequencer.prototype.startThread = function (thread) {
// move to done.
if (thread.status === Thread.STATUS_RUNNING &&
thread.peekStack() === currentBlockId) {
this.proceedThread(thread, currentBlockId);
this.proceedThread(thread);
}
};

View file

@ -69,7 +69,10 @@ Thread.prototype.pushStack = function (blockId) {
// Push an empty stack frame, if we need one.
// Might not, if we just popped the stack.
if (this.stack.length > this.stackFrames.length) {
this.stackFrames.push({});
this.stackFrames.push({
reported: {}, // Collects reported input values.
executionContext: {} // A context passed to block implementations.
});
}
};
@ -99,6 +102,18 @@ Thread.prototype.peekStackFrame = function () {
return this.stackFrames[this.stackFrames.length - 1];
};
/**
* Push a reported value to the parent of the current stack frame.
* @param {!string} inputName Name of input reported.
* @param {!Any} value Reported value to push.
*/
Thread.prototype.pushReportedValue = function (inputName, value) {
var parentStackFrame = this.stackFrames[this.stackFrames.length - 2];
if (parentStackFrame) {
parentStackFrame.reported[inputName] = value;
}
};
/**
* Yields the thread.
*/