7349bd0176
* `sub' to subtract two numbers. * `stringLength' to get the length of a string. * `substring' to get a substring of a string. These should be enough to allow most string operations to be expressed.
26 lines
516 B
Nix
26 lines
516 B
Nix
with builtins;
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rec {
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fold = op: nul: list:
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if list == []
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then nul
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else op (head list) (fold op nul (tail list));
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concat =
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fold (x: y: x + y) "";
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flatten = x:
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if isList x
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then fold (x: y: (flatten x) ++ y) [] x
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else [x];
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sum = fold (x: y: add x y) 0;
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hasSuffix = ext: fileName:
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let lenFileName = stringLength fileName;
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lenExt = stringLength ext;
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in !(lessThan lenFileName lenExt) &&
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substring (sub lenFileName lenExt) lenFileName fileName == ext;
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}
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