Struct void::coreprovider::fmt::Arguments1.0.0[][src]

pub struct Arguments<'a> {
    pieces: &'a [&'a str],
    fmt: Option<&'a [Argument]>,
    args: &'a [ArgumentV1<'a>],
}

This structure represents a safely precompiled version of a format string and its arguments. This cannot be generated at runtime because it cannot safely be done, so no constructors are given and the fields are private to prevent modification.

The format_args! macro will safely create an instance of this structure. The macro validates the format string at compile-time so usage of the write and format functions can be safely performed.

You can use the Arguments<'a> that format_args! returns in Debug and Display contexts as seen below. The example also shows that Debug and Display format to the same thing: the interpolated format string in format_args!.

let debug = format!("{:?}", format_args!("{} foo {:?}", 1, 2));
let display = format!("{}", format_args!("{} foo {:?}", 1, 2));
assert_eq!("1 foo 2", display);
assert_eq!(display, debug);

Fields

Methods

impl<'a> Arguments<'a>
[src]

🔬 This is a nightly-only experimental API. (fmt_internals)

internal to format_args!

When using the format_args!() macro, this function is used to generate the Arguments structure.

🔬 This is a nightly-only experimental API. (fmt_internals)

internal to format_args!

This function is used to specify nonstandard formatting parameters. The pieces array must be at least as long as fmt to construct a valid Arguments structure. Also, any Count within fmt that is CountIsParam or CountIsNextParam has to point to an argument created with argumentusize. However, failing to do so doesn't cause unsafety, but will ignore invalid .

🔬 This is a nightly-only experimental API. (fmt_internals)

internal to format_args!

Estimates the length of the formatted text.

This is intended to be used for setting initial String capacity when using format!. Note: this is neither the lower nor upper bound.

Trait Implementations

impl<'a> Debug for Arguments<'a>
[src]

Formats the value using the given formatter. Read more

impl<'a> Copy for Arguments<'a>
[src]

impl<'a> Clone for Arguments<'a>
[src]

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

impl<'a> Display for Arguments<'a>
[src]

Formats the value using the given formatter. Read more

Auto Trait Implementations

impl<'a> !Send for Arguments<'a>

impl<'a> !Sync for Arguments<'a>