19 lines
428 B
Nix
19 lines
428 B
Nix
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{
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pkgs ? import <nixpkgs> { },
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feature,
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}:
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pkgs.runCommandNoCC "${feature}-present-structured"
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{
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__structuredAttrs = true;
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requiredSystemFeatures = [ feature ];
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}
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''
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if [[ -e /${feature}-files ]]; then
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touch $out
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else
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echo "The host declares ${feature} support, but doesn't expose /${feature}-files" >&2
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echo "Do we fail to parse __structuredAttrs=true derivations?" >&2
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fi
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''
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