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6527cbe107
Added function to std.format to make an educated guess at the length of the resulting string, use that data to reserve capacity in the appender before anything is written to it.
25 lines
No EOL
842 B
Text
25 lines
No EOL
842 B
Text
`std.format` with strings passed during compile-time has been optimized
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Giving $(REF format, std, format) a string as a template parameter allows
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the type correctness of the parameters to be checked at compile time:
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-------
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import std.format : format;
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auto s1 = format!"%d"(4); // works fine
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auto s2 = format("%d"); // runtime exception
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auto s3 = format!"%d"(); // compile time error
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-------
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Now, using this overload also allows std.format to make an educated guess at
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the length of the resulting string, reducing the total number of reallocations
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made to the output buffer.
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-------
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import std.format : format;
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auto s1 = format!"%02d:%02d:%02d"(10, 30, 50); // known for certain to be 8 chars long
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auto s2 = format!"%s %d"("Error Code: ", 42); // Makes an educated guess
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-------
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Longer format strings benefit the most from this change. |