mirror of
https://github.com/fish-shell/fish-shell
synced 2024-12-27 21:33:09 +00:00
43 lines
1.4 KiB
Markdown
43 lines
1.4 KiB
Markdown
# fish-printf
|
|
|
|
The printf implementation used in [fish-shell](https://fishshell.com), based on musl printf.
|
|
|
|
[![crates.io](https://img.shields.io/crates/v/fish-printf.svg)](https://crates.io/crates/fish-printf)
|
|
|
|
Licensed under the MIT license.
|
|
|
|
### Usage
|
|
|
|
Run `cargo add fish-printf` to add this crate to your `Cargo.toml` file.
|
|
|
|
### Notes
|
|
|
|
fish-printf attempts to match the C standard for printf. It supports the following features:
|
|
|
|
- Locale-specific formatting (decimal point, thousands separator, etc.)
|
|
- Honors the current rounding mode.
|
|
- Supports the `%n` modifier for counting characters written.
|
|
|
|
fish-printf does not support positional arguments, such as `printf("%2$d", 1, 2)`.
|
|
|
|
Prefixes like `l` or `ll` are recognized, but only used for validating the format string.
|
|
The size of integer values is taken from the argument type.
|
|
|
|
fish-printf can output to an `std::fmt::Write` object, or return a string.
|
|
|
|
For reasons related to fish-shell, fish-printf has a feature "widestring" which uses the [widestring](https://crates.io/crates/widestring) crate. This is off by default. If enabled, run `cargo add widestring` to add the widestring crate.
|
|
|
|
### Examples
|
|
|
|
```rust
|
|
use fish_printf::sprintf;
|
|
|
|
// Create a `String` from a format string.
|
|
let s = sprintf!("%0.5g", 123456.0) // 1.2346e+05
|
|
|
|
// Append to an existing string.
|
|
let mut s = String::new();
|
|
sprintf!(=> &mut s, "%0.5g", 123456.0) // 1.2346e+05
|
|
```
|
|
|
|
See the crate documentation for additional examples.
|