The avatar for @adg29
Alan David Garcia
Published
Edited
Sep 11, 2019
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md`# Javascript Numbers
Converting a string that contains a number to a Number in JavaScript has many approaches. Heres a notebook with some interesting edgecases, inspired by a tweet you can follow at https://twitter.com/bitandbang/status/1171615896374321152`
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md `## Number
It's a good approach to use the Number constructor to do this. Think of Boolean(thing) vs. !!thing. Using a constructor explicitly conveys what you're trying to do.`
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Number("1")
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new Number("1")
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Number("123xyz")
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["1", "2", "3"].map(Number)
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md `## unary operator`
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+"1"
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+"1.3"
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md `## parseInt`
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parseInt("123xyz")
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parseInt(010)
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["1", "2", "3"].map(parseInt)
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md `For more context on parseInt and map see https://wsvincent.com/javascript-parseint-map/`
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md `## parseFloat`
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["1", "2", "3"].map(parseFloat)
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md `## uint32, unsigned 32bit integer`
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"1" >>> 0
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md `## int32, Signed 32bit integer`
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"2.3" >> 0
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"2.3"|0
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md `## Double bitwise NOT`
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~~"2.3"
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~~"1"
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md `For more context on the double bitwise NOT operator see https://j11y.io/cool-stuff/double-bitwise-not/`
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