19 lines
1.5 KiB
Markdown
19 lines
1.5 KiB
Markdown
---
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{
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.title = "Rob Pike's 5 Rules of Programming",
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.date = @date("2024-05-11T00:00:00"),
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.author = "koehr",
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.draft = false,
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.layout = "til.html",
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.description = "",
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.tags = [],
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.custom = { .source = "https://users.ece.utexas.edu/~adnan/pike.html" },
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}
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---
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1. You can't tell where a program is going to spend its time. Bottlenecks occur in surprising places, so don't try to second guess and put in a speed hack until you've proven that's where the bottleneck is.
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2. Measure. Don't tune for speed until you've measured, and even then don't unless one part of the code overwhelms the rest.
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3. Fancy algorithms are slow when n is small, and n is usually small. Fancy algorithms have big constants. Until you know that n is frequently going to be big, don't get fancy. (Even if n does get big, use Rule 2 first.)
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4. Fancy algorithms are buggier than simple ones, and they're much harder to implement. Use simple algorithms as well as simple data structures.
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5. Data dominates. If you've chosen the right data structures and organized things well, the algorithms will almost always be self-evident. Data structures, not algorithms, are central to programming.
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Pike's rules 1 and 2 restate Tony Hoare's famous maxim "Premature optimization is the root of all evil." Ken Thompson rephrased Pike's rules 3 and 4 as "When in doubt, use brute force.". Rules 3 and 4 are instances of the design philosophy KISS. Rule 5 was previously stated by Fred Brooks in The Mythical Man-Month. Rule 5 is often shortened to "write stupid code that uses smart objects".
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