[−][src]Struct const_format::fmt::DebugStruct
A helper struct for debug formatting a braced struct, or braced variant.
Example
This example demonstrates how you can debug format a struct, and a braced variant.
#![feature(const_mut_refs)] use const_format::{Error, Formatter}; use const_format::{call_debug_fmt, coerce_to_fmt, formatc, impl_fmt, try_}; fn main() { const STRUC: &str = formatc!("{:?}", Foo { a: 5, b: [8, 13, 21], c: "34" }); const ENUM_: &str = formatc!("{:?}", Bar::Baz { d: false, e: None }); assert_eq!(STRUC, "Foo { a: 5, b: [8, 13, 21], c: \"34\" }"); assert_eq!(ENUM_, "Baz { d: false, e: None }"); } struct Foo{ a: u32, b: [u32; 3], c: &'static str, } enum Bar { Baz{ d: bool, e: Option<bool>, } } impl_fmt!{ impl Foo; const fn const_debug_fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error> { let mut f = f.debug_struct("Foo"); try_!(coerce_to_fmt!(&self.a).const_debug_fmt(f.field("a"))); try_!(coerce_to_fmt!(&self.b).const_debug_fmt(f.field("b"))); try_!(coerce_to_fmt!(&self.c).const_debug_fmt(f.field("c"))); f.finish() } } impl_fmt!{ impl Bar; const fn const_debug_fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error> { match self { Bar::Baz{d, e} => { let mut f = f.debug_struct("Baz"); // This macro allows debug formatting some generic types that // don't have a const_debug_fmt fn, like Options which wrap non-std types. call_debug_fmt!(std, d, f.field("d")); call_debug_fmt!(Option, e, f.field("e")); f.finish() } } } }
Implementations
impl<'f, 'w> DebugStruct<'f, 'w>
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pub const fn field(&mut self, name: &str) -> &mut Formatter<'w>
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Adds a field to the formatted output.
pub const fn finish(self) -> Result<(), Error>
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Finishes writing the struct/variant,
and if anything went wrong in the field
method,returns an error.
Auto Trait Implementations
impl<'f, 'w> RefUnwindSafe for DebugStruct<'f, 'w>
impl<'f, 'w> Send for DebugStruct<'f, 'w>
impl<'f, 'w> Sync for DebugStruct<'f, 'w>
impl<'f, 'w> Unpin for DebugStruct<'f, 'w> where
'w: 'f,
'w: 'f,
impl<'f, 'w> !UnwindSafe for DebugStruct<'f, 'w>
Blanket Implementations
impl<T> Any for T where
T: 'static + ?Sized,
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T: 'static + ?Sized,
impl<T> Borrow<T> for T where
T: ?Sized,
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T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
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T: ?Sized,
fn borrow_mut(&mut self) -> &mut T
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impl<T> From<T> for T
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impl<T, U> Into<U> for T where
U: From<T>,
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U: From<T>,
impl<T, U> TryFrom<U> for T where
U: Into<T>,
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U: Into<T>,
type Error = Infallible
The type returned in the event of a conversion error.
fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>
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impl<T, U> TryInto<U> for T where
U: TryFrom<T>,
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U: TryFrom<T>,