Struct BudgetedStringWriter 

pub struct BudgetedStringWriter<'a, R, Q = u64>
where
    Q: ResourceQuantity,
{ /* private fields */ }

Collects a UTF-8 string while checking a finite byte budget incrementally.

The writer is constructed and committed by ResourceBudget::try_write_string. A failed render drops the buffered prefix and leaves the budget unchanged.

Use Self::as_fmt for formatting APIs or Self::as_io for byte-oriented I/O. The returned adapter borrows this writer, so the render callback must finish using it before returning.

Type Parameters

• R - Caller-defined resource identity retained by limits and errors.
• Q - Exact unsigned quantity used for measurements and accounting.

Examples

use std::fmt::Write as _;
use qubit_budget::ResourceBudget;

let mut budget = ResourceBudget::new("response bytes", 16_u64);
let output = budget
    .try_write_string(|writer| {
        let mut formatted = writer.as_fmt();
        write!(&mut formatted, "status={}", 200)
    })
    .expect("the rendered response should fit");

assert_eq!(output, "status=200");
assert_eq!(budget.used(), 10);

Implementations

impl<'a, R, Q> BudgetedStringWriter<'a, R, Q>

where R: Clone, Q: ResourceQuantity,

pub fn as_fmt(&mut self) -> impl Write + '_

Returns a formatting writer view over the current transaction.

Returns

Returns a formatting writer view over the current transaction.

pub fn as_io(&mut self) -> impl Write + '_

Returns an I/O writer view over the current transaction.

Returns

Returns an I/O writer view over the current transaction.