couple of clippy::style changes

[matthiaskrgr]

comparison_to_empty
iter_nth_zero
for_kv_map
manual_next_back
redundant_pattern

get_first
single_char_add_str
unnecessary_mut_passed
manual_map
manual_is_ascii_check

[rustbot]

r? @eholk

(rustbot has picked a reviewer for you, use r? to override)

[rustbot]

Some changes occurred to the core trait solver

cc @rust-lang/initiative-trait-system-refactor

[fee1-dead]

Suggested change

	first.is_ascii_digit()
	self.ident.as_str().as_bytes()[0].is_ascii_digit()

[fee1-dead]

Suggested change

	s
	format!("[{}]", v.join(", "))

[fee1-dead]

r? @fee1-dead
@rustbot author

[matthiaskrgr]

@rustbot ready

[fee1-dead]

@bors r+ rollup

[fee1-dead]

@bors r+ rollup

[bors]

📌 Commit af2b370 has been approved by fee1-dead

It is now in the queue for this repository.

[bors]

⌛ Testing commit af2b370 with merge 155a5c2...

[bors]

☀️ Test successful - checks-actions
Approved by: fee1-dead
Pushing 155a5c2 to master...

[rust-timer]

Finished benchmarking commit (155a5c2): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

Instruction count

This benchmark run did not return any relevant results for this metric.

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-2.8%	[-2.8%, -2.8%]	1
All ❌✅ (primary)	-	-	0

Cycles

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.2%	[2.2%, 2.2%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-2.0%	[-2.0%, -2.0%]	1
All ❌✅ (primary)	-	-	0

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 652.153s -> 652.237s (0.01%)