91 lines
2.3 KiB
JavaScript
91 lines
2.3 KiB
JavaScript
"use strict";
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const assert = require("assert").strict;
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function repeat(s, n)
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{
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let out = "";
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for(let i = 0; i < n; i++) out += s;
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return out;
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}
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function indent(lines, how_much)
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{
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return lines.map(line => repeat(" ", how_much) + line);
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}
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function print_syntax_tree(statements)
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{
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let code = [];
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for(let statement of statements)
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{
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if(typeof statement === "string")
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{
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code.push(statement);
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}
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else if(statement.type === "switch")
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{
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assert(statement.condition);
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const cases = [];
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for(let case_ of statement.cases)
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{
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assert(case_.conditions.length >= 1);
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cases.push(case_.conditions.join(" | ") + " => {");
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cases.push.apply(cases, indent(print_syntax_tree(case_.body), 4));
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cases.push(`},`);
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}
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if(statement.default_case)
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{
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cases.push(`_ => {`);
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cases.push.apply(cases, indent(print_syntax_tree(statement.default_case.body), 4));
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cases.push(`}`);
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}
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code.push(`match ${statement.condition} {`);
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code.push.apply(code, indent(cases, 4));
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code.push(`}`);
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}
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else if(statement.type === "if-else")
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{
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assert(statement.if_blocks.length >= 1);
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let first_if_block = statement.if_blocks[0];
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code.push(`if ${first_if_block.condition} {`);
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code.push.apply(code, indent(print_syntax_tree(first_if_block.body), 4));
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code.push(`}`);
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for(let i = 1; i < statement.if_blocks.length; i++)
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{
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let if_block = statement.if_blocks[i];
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code.push(`else if ${if_block.condition} {`);
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code.push.apply(code, indent(print_syntax_tree(if_block.body), 4));
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code.push(`}`);
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}
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if(statement.else_block)
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{
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code.push(`else {`);
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code.push.apply(code, indent(print_syntax_tree(statement.else_block.body), 4));
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code.push(`}`);
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}
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}
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else
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{
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assert(false, "Unexpected type: " + statement.type, "In:", statement);
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}
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}
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return code;
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}
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module.exports = {
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print_syntax_tree,
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};
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