size_hint.rs - source

Files

aho_corasick

packed

teddy

compile.rs mod.rs runtime.rs

api.rs mod.rs pattern.rs rabinkarp.rs vector.rs

ahocorasick.rs automaton.rs buffer.rs byte_frequencies.rs classes.rs dfa.rs error.rs lib.rs nfa.rs prefilter.rs state_id.rs

anyhow

backtrace.rs chain.rs context.rs error.rs fmt.rs kind.rs lib.rs macros.rs ptr.rs wrapper.rs

drone_config

config.rs format.rs lib.rs

drone_core

bitfield

ffi

c_str.rs c_string.rs libc.rs mod.rs

fib

chain.rs closure.rs future.rs generator.rs mod.rs stream_pulse.rs stream_ring.rs

heap

allocator.rs mod.rs pool.rs

io

mod.rs read.rs seek.rs write.rs

log

macros.rs mod.rs port.rs

reg

field.rs marker.rs mod.rs prelude.rs tag.rs

sync

spsc

oneshot

mod.rs receiver.rs sender.rs

pulse

mod.rs receiver.rs sender.rs

ring

mod.rs receiver.rs sender.rs

linked_list.rs mod.rs mutex.rs

thr

soft

exec.rs mod.rs prelude.rs

inventory.rs lang_items.rs lib.rs mem.rs periph.rs prelude.rs proc_loop.rs token.rs

drone_core_macros

bitfield.rs config_override.rs heap.rs lib.rs log_baud_rate.rs periph.rs periph_map.rs periph_singular.rs reg.rs reg_assert_taken.rs reg_tokens.rs reg_tokens_inner.rs simple_token.rs simple_tokens.rs static_tokens.rs thr_pool.rs thr_soft.rs

drone_ctypes

drone_macros_core

cfg_cond.rs lib.rs macros.rs unkeywordize.rs

futures

futures_channel

lib.rs lock.rs oneshot.rs

futures_core

task

__internal

atomic_waker.rs mod.rs

future.rs lib.rs stream.rs

futures_io

futures_macro

join.rs lib.rs select.rs

futures_sink

futures_task

arc_wake.rs future_obj.rs lib.rs noop_waker.rs spawn.rs waker.rs waker_ref.rs

futures_util

async_await

join_mod.rs mod.rs pending.rs poll.rs select_mod.rs

future

lock

bilock.rs mod.rs

sink

buffer.rs close.rs drain.rs err_into.rs fanout.rs feed.rs flush.rs map_err.rs mod.rs send.rs send_all.rs unfold.rs with.rs with_flat_map.rs

stream

task

mod.rs spawn.rs

fns.rs lib.rs never.rs unfold_state.rs

if_chain

inflector

cases

camelcase

case

classcase

kebabcase

pascalcase

screamingsnakecase

sentencecase

snakecase

tablecase

titlecase

traincase

numbers

deordinalize

ordinalize

string

constants

deconstantize

demodulize

pluralize

singularize

suffix

foreignkey

lazy_static

inline_lazy.rs lib.rs

memchr

x86

avx.rs mod.rs sse2.rs

fallback.rs iter.rs lib.rs naive.rs

pin_project_lite

pin_utils

lib.rs projection.rs stack_pin.rs

proc_macro2

detection.rs fallback.rs lib.rs marker.rs parse.rs wrapper.rs

proc_macro_hack

error.rs iter.rs lib.rs parse.rs quote.rs

proc_macro_nested

quote

ext.rs format.rs ident_fragment.rs lib.rs runtime.rs spanned.rs to_tokens.rs

regex

regex_syntax

serde

de

ignored_any.rs impls.rs mod.rs seed.rs utf8.rs value.rs

private

de.rs doc.rs mod.rs ser.rs size_hint.rs

ser

fmt.rs impls.rs impossible.rs mod.rs

integer128.rs lib.rs macros.rs

serde_derive

internals

ast.rs attr.rs case.rs check.rs ctxt.rs mod.rs receiver.rs respan.rs symbol.rs

bound.rs de.rs dummy.rs fragment.rs lib.rs pretend.rs ser.rs try.rs

syn

toml

datetime.rs de.rs lib.rs macros.rs map.rs ser.rs spanned.rs tokens.rs value.rs

typenum

array.rs bit.rs int.rs lib.rs marker_traits.rs operator_aliases.rs private.rs type_operators.rs uint.rs

unicode_xid

lib.rs tables.rs

use lib::*;

pub fn from_bounds<I>(iter: &I) -> Option<usize>
where
    I: Iterator,
{
    helper(iter.size_hint())
}

#[cfg(any(feature = "std", feature = "alloc"))]
#[inline]
pub fn cautious(hint: Option<usize>) -> usize {
    cmp::min(hint.unwrap_or(0), 4096)
}

fn helper(bounds: (usize, Option<usize>)) -> Option<usize> {
    match bounds {
        (lower, Some(upper)) if lower == upper => Some(upper),
        _ => None,
    }
}