SandboXP

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"use strict";
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const assert = require("assert").strict;
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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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