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33 lines
731 B
33 lines
731 B
/*
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* An environment is just an object that maps identifiers to JLambda expressions
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* with a few built-in (a standard Prelude environment)
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*/
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import errors from "./errors.js";
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import rep from "./representation.js";
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// creates a new environment initialized with the pairs in values
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function makeEnv(name, values) {
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var env = {};
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env.name = name;
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env.bindings = {};
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for (var i = 0; i < values.length; i++) {
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name = values[i][0];
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var val = values[i][1];
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env.bindings[name] = val;
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}
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return env;
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}
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function lookup(name, env) {
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var value = env.bindings[name];
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if (!value) {
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throw errors.JUnboundError(name, env.name);
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}
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return value;
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}
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export default {
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lookup : lookup,
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makeEnv : makeEnv
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};
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