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Simplify desugared form

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Before:
```
[ inherit (attrs) a b c; ] := builtins.attrValues { inherit (attrs) a b c; }
```

After:
```
[ inherit (attrs) a b c; ] := [ attrs.a attrs.b attrs.c ];
```

The previous desugaring has some potentially nice properties such as
non-significant ordering and no-duplicate enforcement, but was
ultimately deemed unintuitive and too surprising in practical use.
This commit is contained in:
Ryan Burns 2021-10-19 19:37:14 -07:00
parent 2a6bbb49f1
commit ad09702fd4
1 changed files with 8 additions and 10 deletions
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18
rfcs/0110-inherit-as-list.md
View file

@ -65,8 +65,8 @@ The proposed syntax is:
These expressions are (respectively) syntactic sugar for:
```nix
builtins.attrValues { inherit (attrs) a b c; }
builtins.attrValues { inherit a b c; }
[ attrs.a attrs.b attrs.c ]
[ a b c ]
```
The `inherit` keyword is intentionally reused so as to not add any new
@ -112,17 +112,15 @@ buildInputs = [
];
```
Sinc attributes inherit from the current scope with `{ inherit a b c; }`,
this RFC proposes a corresponding list-inherit syntax which also inherits
from the current scope. So if the order of the ordinary elements in the
previous list is not significant, one could rewrite the list as:
The order of the elements is preserved inside of and between inherits,
so the previous is exactly equivalent to
```
buildInputs = [
inherit a b c;
inherit (pkgsFoo) d e f;
inherit g h i;
inherit (pkgsBar) j k l;
a b c
pkgsFoo.d pkgsFoo.e pkgsFoo.f
g h i
pkgsBar.j pkgsBar.k pkgsBar.l
];
```