37 lines
988 B
JavaScript
37 lines
988 B
JavaScript
// https://babeljs.io/docs/en/babel-plugin-proposal-numeric-separator
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let budget = 1_000_000_000_000;
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// What is the value of `budget`? It's 1 trillion!
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//
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// Let's confirm:
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console.log(budget === 10 ** 12); // true
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let nibbles = 0b1010_0001_1000_0101;
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// Is bit 7 on? It sure is!
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// 0b1010_0001_1000_0101
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// ^
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//
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// We can double check:
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console.log(!!(nibbles & (1 << 7))); // true
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// Messages are sent as 24 bit values, but should be
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// treated as 3 distinct bytes:
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let message = 0xa0_b0_c0;
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// What's the value of the upper most byte? It's A0, or 160.
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// We can confirm that:
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let a = (message >> 16) & 0xff;
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console.log(a.toString(16), a); // a0, 160
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// What's the value of the middle byte? It's B0, or 176.
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// Let's just make sure...
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let b = (message >> 8) & 0xff;
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console.log(b.toString(16), b); // b0, 176
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// What's the value of the lower most byte? It's C0, or 192.
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// Again, let's prove that:
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let c = message & 0xff;
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console.log(c.toString(16), b); // c0, 192
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