Struct FormatterBuilder 

pub struct FormatterBuilder { /* private fields */ }

Formatter safe builder.

The safe and stable builder for fmt::Formatter

Due to unstable Formatter::new, uses this crate to dynamically build a Formatter.

Examples

use formatter_builder::{FormatterBuilder, Fill, Sign, Alignment};

let mut output = String::new();
let n = 6.23;
formatter_builder::FormatterBuilder::new()
    .width(8)
    .align(Alignment::Right)
    .precision(3)
    .fill(Fill::Zero)
    .with(&mut output, |f| {
        std::fmt::Display::fmt(&n, f)
    })
    .unwrap();
assert_eq!(output, "0006.230")

Implementations

impl FormatterBuilder

pub fn with<W, F>(&self, writer: W, f: F) -> Result

where W: Write, F: FnOnce(&mut Formatter<'_>) -> Result,

impl FormatterBuilder

pub fn new() -> Self

pub fn sign(&mut self, sign: impl Into<Option<Sign>>) -> &mut Self

Format like {:+} and {:-}

Examples

use std::fmt::Display;
let mut writter = String::new();
FormatterBuilder::new().sign(Sign::Plus).with(&mut writter, |f| {
    2i32.fmt(f);
    Ok(())
}).unwrap();
assert_eq!(writter, "+2");

pub fn sign_aware_zero_pad(&mut self, sign_aware_zero_pad: bool) -> &mut Self

Format like {:0}

Examples

FormatterBuilder::new().sign_aware_zero_pad(true).with(writter, |f| {
    assert!(f.sign_aware_zero_pad());
    Ok(())
}).unwrap();

pub fn alternate(&mut self, alternate: bool) -> &mut Self

Format like {:#}

Examples

FormatterBuilder::new().alternate(true).with(writter, |f| {
    assert!(f.alternate());
    Ok(())
}).unwrap();

pub fn fill(&mut self, fill: impl Into<Option<Fill>>) -> &mut Self

Format like {:0>} {: ^} etc

Panics

• panic when align is unset

Examples

FormatterBuilder::new().align(Left).fill(Fill::Space).with(writter, |f| {
    assert_eq!(f.fill(), ' ');
    Ok(())
}).unwrap();

pub fn align(&mut self, align: impl Into<Option<Alignment>>) -> &mut Self

Format like {:<} and {:^} and {:>}

Examples

FormatterBuilder::new().align(Center).with(writter, |f| {
    assert_eq!(f.align(), Some(Center));
    Ok(())
}).unwrap();

pub fn width(&mut self, width: impl Into<Option<u16>>) -> &mut Self

Format like {:3}

Examples

use std::fmt::Display;
let mut writter = String::new();
FormatterBuilder::new().width(3).with(&mut writter, |f| {
    2i32.fmt(f);
    Ok(())
}).unwrap();
assert_eq!(writter, "  2");

pub fn precision(&mut self, precision: impl Into<Option<u16>>) -> &mut Self

Format like {:.3}

Examples

use std::fmt::Display;
let mut writter = String::new();
FormatterBuilder::new().precision(3).with(&mut writter, |f| {
    2f32.fmt(f);
    Ok(())
}).unwrap();
assert_eq!(writter, "2.000");

Trait Implementations

impl Debug for FormatterBuilder

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for FormatterBuilder

fn default() -> FormatterBuilder

Returns the “default value” for a type.