21 lines
523 B
Nix
21 lines
523 B
Nix
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{ lib, ... }:
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{
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# returns matching part of _regex_ _string_; null indicates failure.
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rgxToString = regex: string:
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let
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match =
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let
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head = lib.substring 0 1 regex;
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sec = lib.substring 1 2 regex;
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in
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if head == "^"
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|| head == "."
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|| (sec == "*" || sec == "+" || sec == "?")
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then builtins.match "(${regex}).*" string
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else builtins.match ".*(${regex}).*" string;
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in
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if lib.isList match
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then lib.head match
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else null;
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}
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