51 lines
1.8 KiB
JavaScript
51 lines
1.8 KiB
JavaScript
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import BaseJSNode from './BaseJSNode.js';
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export default class SwitchStatement extends BaseJSNode {
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run() {
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const discriminant = this.visitor.visitNode(this.node.discriminant);
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let matched = false;
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let default_case = -1;
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let index = 0;
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while (true) {
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const _case = this.node.cases[index];
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if (matched) {
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const result = this.visitor.visitNode(_case);
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// If it's a break then stop here.
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if (result === 'break') {
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break;
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}
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// Switch statements do not support continue, but it can be used when inside a while/for loop.
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if (result === 'continue') {
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return result;
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}
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++index;
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if (index >= this.node.cases.length) {
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index = 0;
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break;
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}
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else {
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continue;
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}
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}
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matched = _case && (discriminant === this.visitor.visitNode(_case.test));
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// Ran through all cases and checked everything, break the loop.
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if (matched === undefined && index > this.node.cases.length)
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break;
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// Save the default case so we can get back to it later.
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if (_case && !matched && !_case.test) {
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default_case = index;
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index += 1;
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continue;
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}
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// Ran through all cases but no match — run default case.
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if (!_case && !matched && default_case !== -1) {
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matched = true;
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index = default_case;
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continue;
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}
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if (!matched) {
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++index;
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}
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}
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}
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}
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