diff options
Diffstat (limited to 'demo/demo.js')
| -rw-r--r-- | demo/demo.js | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/demo/demo.js b/demo/demo.js new file mode 100644 index 00000000..069927d7 --- /dev/null +++ b/demo/demo.js @@ -0,0 +1,205 @@ +/* + * Copyright 2016 WebAssembly Community Group participants + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +var defaultIndent = ' '; +var input = document.getElementById('input'); +var output = document.getElementById('output'); +var select = document.getElementById('select'); + +function debounce(f, wait) { + var lastTime = 0; + var timeoutId = -1; + var wrapped = function() { + var time = +new Date(); + if (time - lastTime < wait) { + if (timeoutId == -1) + timeoutId = setTimeout(wrapped, (lastTime + wait) - time); + return; + } + if (timeoutId != -1) + clearTimeout(timeoutId); + timeoutId = -1; + lastTime = time; + f.apply(null, arguments); + }; + return wrapped; +} + +function insertTextAtSelection(input, src) { + var selectionStart = input.selectionStart; + var selectionEnd = input.selectionEnd; + var oldValue = input.value; + input.value = oldValue.slice(0, selectionStart) + src + + oldValue.slice(selectionEnd); + input.selectionStart = input.selectionEnd = selectionStart + src.length; +} + +function onInputKeyDown(e) { + if (e.keyCode == 9) { // tab + insertTextAtSelection(this, defaultIndent); + e.preventDefault(); + } else if (e.keyCode == 13) { // newline + // count nesting depth + var parens = 0; + var lastOpen = -1; + var indent = ''; + for (var i = this.selectionStart - 1; i >= 0; --i) { + var c = this.value[i]; + if (c == '(') { + if (--parens < 0) { + if (lastOpen != -1) + i = lastOpen; + else + indent = defaultIndent; + break; + // find first sibling "(", if any + } else if (parens == 0 && lastOpen == -1) { + lastOpen = i; + } + } else if (c == ')') { + parens++; + } + } + // get column of current nesting + var col = 0; + for (; i > 0; --i) { + var c = this.value[i]; + if (c == '\n') { + col--; // went back too far + break; + } else { + col++; + } + } + // write newline, plus indentation + insertTextAtSelection(this, '\n' + ' '.repeat(col) + indent); + e.preventDefault(); + } +} + +function onError(loc, error, sourceLine, sourceLineColumnOffset) { + var lines = [ + loc.filename + ':' + loc.line + ':' + loc.firstColumn, + error + ]; + if (sourceLine.length > 0) { + var numSpaces = loc.firstColumn - 1 - sourceLineColumnOffset; + var numCarets = loc.lastColumn - loc.firstColumn; + lines.push(sourceLine); + lines.push(' '.repeat(numSpaces) + '^'.repeat(numCarets)); + } + output.textContent += lines.join('\n') + '\n'; +} + +var allocator = wasm.LibcAllocator; +var eh = new wasm.SourceErrorHandler(onError, 80); + +function compile(text) { + output.textContent = ''; + try { + var buf = wasm.Buffer.fromString(text); + var lexer = wasm.Lexer.fromBuffer(allocator, 'test.wast', buf); + var script = wasm.parse(lexer, eh); + wasm.checkAst(lexer, script, eh); + var memoryWriter = new wasm.MemoryWriter(allocator); + var jsWriter = new wasm.JSStringWriter(); + var logStream = new wasm.Stream(jsWriter.writer); + var options = new wasm.WriteBinaryOptions({logStream: logStream}); + wasm.writeBinaryScript(allocator, memoryWriter.base, script, options); + output.textContent = jsWriter.string; + } catch (e) { + output.textContent += e.toString(); + } finally { + if (options) + options.$destroy(); + if (logStream) + logStream.$destroy(); + if (script) + script.$destroy(); + if (jsWriter) + jsWriter.$destroy(); + if (memoryWriter) + memoryWriter.$destroy(); + if (lexer) + lexer.$destroy(); + if (buf) + buf.$destroy(); + } +} + +var compileInput = debounce(function() { compile(input.value); }, 100); + +function onInputInput(e) { + compileInput(); +} + +var examples = [ + { + name: 'empty', + contents: '(module)' + }, + + { + name: 'simple', + contents: + '(module\n' + + ' (func $addTwo (param i32 i32) (result i32)\n' + + ' (i32.add\n' + + ' (get_local 0)\n' + + ' (get_local 1)))\n' + + ' (export "addTwo" $addTwo))\n' + }, + + { + name: 'factorial', + contents: + '(module\n' + + ' (func $fac (param i64) (result i64)\n' + + ' (if (i64.lt_s (get_local 0) (i64.const 0))\n' + + ' (then (i64.const 1))\n' + + ' (else\n' + + ' (i64.mul\n' + + ' (get_local 0)\n' + + ' (call $fac\n' + + ' (i64.sub\n' + + ' (get_local 0)\n' + + ' (i64.const 1)))))))\n' + + ' (export "fac" $fac))\n' + } +]; + +function setExample(index) { + var contents = examples[index].contents; + input.value = contents; + compileInput(); +} + +function onSelectChanged(e) { + setExample(this.selectedIndex); +} + +input.addEventListener('keydown', onInputKeyDown); +input.addEventListener('input', onInputInput); +select.addEventListener('change', onSelectChanged); + +for (var i = 0; i < examples.length; ++i) { + var example = examples[i]; + var option = document.createElement('option'); + option.textContent = example.name; + select.appendChild(option); +} +select.selectedIndex = 1; +setExample(select.selectedIndex); |