Fixes#18583.
## Problem
Several stdlib collection types compute the separator for `$` using
`result.len > 1`, where `result` starts as the opening bracket (`"["` or
`"{"`). This breaks when a collection element type has a `$` that
returns an empty string: `result.len` stays at 1 after the first item
contributes nothing, so the separator is never inserted for subsequent
items.
```nim
import std/deques
type Test = object
proc `$`(x: Test): string = ""
echo [Test(), Test()].toDeque # prints [] — expected [, ]
```
## Fix
Replace the length check with an explicit `first` flag in all affected
modules: `deques`, `heapqueue`, `lists`, `critbits`, and `strtabs`.
## Tests
Regression tests added to `tdeques`, `theapqueue`, and `tlists` using a
local type whose `$` returns `""`. All three test files pass with `nim c
-r`.
## Notes
I work with Claude as a co-processor. I'm 56, came to programming late,
and this is genuinely how I learn and contribute. I understand what I'm
submitting, but I didn't write it alone. If your project prefers
human-only contributions, just say so and I'll close without friction.
---------
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
fixes#25240
> Deque items behavior is not the same on 2.0.16 and 2.2.0
The behavior seems to be caused by the temp introduced for the parameter
`deq.len`, which prevents it from being evaluated multiple times
It seems Deque doesn't need `mask` field because `data.len - 1` equals
to `mask`.
Deque without `mask` field passes test `tests/stdlib/tdeques.nim`.
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
* CIs: attempt to use csources_v1
* also updated the BSDs
* also updated azure pipelines
* std modules should not itself use the 'std/' import dir...
* compiler has to be careful with std/ for v1 booting
* use sink and lent in deques
* Update lib/pure/collections/deques.nim
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
This commit polishes the new proc introduced by d9ed816b10.
Changes:
- Rename to `toDeque` for more consistency with well-known procs like
`toHashSet` and `toTable`.
- Rename the `openArray` parameter. The name `arr` was potentially less
clear given that the proc can be used with a seq (or string).
- Add a `since` annotation.
- Reword the doc comment, and clarify that ordering is preserved.
- Add runnableExamples.
- Add "see also" cross linking between `initDeque` and `toDeque`.
- Remove duplicate `nextPowerOfTwo`. The `initImpl` template already
includes it.
- Implement the proc using the `items` iterator, rather than indexing.
This matches the implementation of `sets.toHashSet` and
`tables.toTable`.
- Add a test within `when isMainModule`.
- Add a changelog entry.
* Add ability to initialize a deque with a sequence
Example:
var dq = initDeque[char](@['a', 'b', 'c'])
* Update deques.nim
* Optimized deque initialization
* Sequence replaced by open array in deque initialization
* remove a condition that table size must be passed as power of 2
* remove power-of-2 condition from sets and sharedtables
* remove power-of-2 condition from deques
* use 'correctSize' for both branches
* prettify changelog.md and fix typos
* add a changelog entry
* fix double-call of 'right-size'
* fix the same thing in sets.nim
* introduce a new internal proc `slotsNeeded`
Deprecate the public proc `rightSize`, which is not needed anymore.
Now it is an identity function, allowing the old code to work
correctly and without extra allocations.
* Error -> Defect for defects
The distinction between Error and Defect is subjective,
context-dependent and somewhat arbitrary, so when looking at an
exception, it's hard to guess what it is - this happens often when
looking at a `raises` list _without_ opening the corresponding
definition and digging through layers of inheritance.
With the help of a little consistency in naming, it's at least possible
to start disentangling the two error types and the standard lib can set
a good example here.
* Add deques.peekFirst/Last(var Deque[T]) -> var T
* Add changelog entry for deques.peekFirst/Last var T overloads
* Add since annotation to peekFirst/peekLast
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
