mirror of
https://github.com/privatevoid-net/nix-super.git
synced 2024-11-10 08:16:15 +02:00
d0f2da214b
* Clarify the documentation of foldl': That the arguments are forced before application (?) of `op` is necessarily true. What is important to stress is that we force every application of `op`, even when the value turns out to be unused. * Move the example before the comment about strictness to make it less confusing: It is a general example and doesn't really showcase anything about foldl' strictness. * Add test cases which nail down aspects of foldl' strictness: * The initial accumulator value is not forced unconditionally. * Applications of op are forced. * The list elements are not forced unconditionally.
9 lines
201 B
Nix
9 lines
201 B
Nix
# Tests that the rhs argument of op is not forced unconditionally
|
|
let
|
|
lst = builtins.foldl'
|
|
(acc: x: acc ++ [ x ])
|
|
[ ]
|
|
[ 42 (throw "this shouldn't be evaluated") ];
|
|
in
|
|
|
|
builtins.head lst
|