Struct const_format::fmt::DebugSet

pub struct DebugSet<'f, 'w> { /* fields omitted */ }

This is supported on crate feature fmt only.

For debug formatting a set.

Example

This example demonstrates how you can debug format a custom type as a set.

#![feature(const_mut_refs)]

use const_format::{Error, Formatter};
use const_format::{formatc, impl_fmt, try_};

use std::ops::Range;

fn main() {
    const SET: &str = formatc!("{:?}", StrSet(&["foo", "bar", "baz"]));
     
    assert_eq!(SET, r#"{"foo", "bar", "baz"}"#);
}

struct StrSet(&'static [&'static str]);

impl_fmt!{
    impl StrSet;
     
    const fn const_debug_fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error> {
        let mut f = f.debug_set();
        let mut i = 0;
        while i < self.0.len() {
            try_!(f.entry().write_str_debug(self.0[i]));
            i+=1;
        }
        f.finish()
    }
}

Implementations

impl<'f, 'w> DebugSet<'f, 'w>

pub const fn entry(&mut self) -> &mut Formatter<'w>

Adds a set entry to the formatted output

pub const fn finish(self) -> Result<(), Error>

Finishes writing the set, and if anything went wrong in the entry method,returns an error.