document builtins.currentTime

This commit is contained in:
Valentin Gagarin 2023-05-11 20:04:16 +02:00
parent dfc393ffd3
commit 549f8dc97b

View file

@ -17,3 +17,26 @@ These constants are built into the Nix language evaluator:
The built-in value `currentSystem` evaluates to the Nix platform
identifier for the Nix installation on which the expression is being
evaluated, such as `"i686-linux"` or `"x86_64-darwin"`.
- [`builtins.currentTime`]{#builtins-currentTime} (integer)
Return the [Unix time](https://en.wikipedia.org/wiki/Unix_time) at first evaluation.
Repeated references to that name will re-use the initially obtained value.
Example:
```console
$ nix repl
Welcome to Nix 2.15.1 Type :? for help.
nix-repl> builtins.currentTime
1683705525
nix-repl> builtins.currentTime
1683705525
```
> **Warning**
>
> This is intended for testing and debugging only.
> Do not use it in production systems, since an impure, that is, non-constant value will break reproducibility.