36 lines
961 B
JavaScript
36 lines
961 B
JavaScript
// objects
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// load math.js (using node.js)
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const { evaluate, format } = require('..')
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// create an object. Keys can be symbols or strings
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print(evaluate('{x: 2 + 1, y: 4}')) // {"x": 3, "y": 4}
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print(evaluate('{"name": "John"}')) // {"name": "John"}
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// create an object containing an object
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print(evaluate('{a: 2, b: {c: 3, d: 4}}')) // {"a": 2, "b": {"c": 3, "d": 4}}
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const scope = {
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obj: {
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prop: 42
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}
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}
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// retrieve properties using dot notation or bracket notation
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print(evaluate('obj.prop', scope)) // 42
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print(evaluate('obj["prop"]', scope)) // 42
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// set properties (returns the whole object, not the property value!)
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print(evaluate('obj.prop = 43', scope)) // 43
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print(evaluate('obj["prop"] = 43', scope)) // 43
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print(scope.obj) // {"prop": 43}
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/**
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* Helper function to output a value in the console. Value will be formatted.
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* @param {*} value
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*/
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function print (value) {
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const precision = 14
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console.log(format(value, precision))
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}
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