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attribute existence and to return an attribute from an attribute
set, respectively. Example: `hasAttr "foo" {foo = 1;}'. They
differ from the `?' and `.' operators in that the attribute name is
an arbitrary expression. (NIX-61)
11 lines
231 B
Nix
11 lines
231 B
Nix
let {
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as = { x = 123; y = 456; } // { z = 789; } // { z = 987; };
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A = "a";
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Z = "z";
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body = if builtins.hasAttr A as
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then builtins.getAttr A as
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else assert builtins.hasAttr Z as; builtins.getAttr Z as;
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}
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