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mention the issue of fallibility in replacements in the API docs #976

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obsgolem opened this issue Apr 12, 2023 · 2 comments
Closed

mention the issue of fallibility in replacements in the API docs #976

obsgolem opened this issue Apr 12, 2023 · 2 comments

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@obsgolem
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Currently the Replacer trait returns a string. If you have complicated replacement logic, there is a decent chance that you want to be able to return a Result or an Option instead, with short circuiting behavior. The API would basically be to add try variants of replace_all and replacen and a new FallibleReplacer trait with an associated Error type.

@BurntSushi
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I think in cases like this, it would be best to just write your own replacement routine. replace_all is not a particularly complicated routine IMO, and I'd really rather folks do that at this point than bloating the API.

This has been discussed somewhat before in #648, and note that I wrote a fallible replacement routine in 10 not-too-complex lines.

@obsgolem
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All right, I am content with that. I feel it might be worth noting that recommendation in the docs. Something like

If the replace operation might fail, consider using implementing the replacement manually with captures_iter.

@BurntSushi BurntSushi added the doc label Apr 15, 2023
@BurntSushi BurntSushi changed the title Short circuiting replace_all mention the issue of fallibility in replacements in the API docs May 24, 2023
BurntSushi added a commit that referenced this issue Jul 5, 2023
I usually close tickets on a commit-by-commit basis, but this refactor
was so big that it wasn't feasible to do that. So ticket closures are
marked here.

Closes #244
Closes #259
Closes #476
Closes #644
Closes #675
Closes #824
Closes #961

Closes #68
Closes #510
Closes #787
Closes #891

Closes #429
Closes #517
Closes #579
Closes #779
Closes #850
Closes #921
Closes #976
Closes #1002

Closes #656
crapStone added a commit to Calciumdibromid/CaBr2 that referenced this issue Jul 18, 2023
This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [regex](https://github.com/rust-lang/regex) | dependencies | minor | `1.8.4` -> `1.9.1` |

---

### Release Notes

<details>
<summary>rust-lang/regex (regex)</summary>

### [`v1.9.1`](https://github.com/rust-lang/regex/blob/HEAD/CHANGELOG.md#191-2023-07-07)

[Compare Source](rust-lang/regex@1.9.0...1.9.1)

\==================
This is a patch release which fixes a memory usage regression. In the regex
1.9 release, one of the internal engines used a more aggressive allocation
strategy than what was done previously. This patch release reverts to the
prior on-demand strategy.

Bug fixes:

-   [BUG #&#8203;1027](rust-lang/regex#1027):
    Change the allocation strategy for the backtracker to be less aggressive.

### [`v1.9.0`](https://github.com/rust-lang/regex/blob/HEAD/CHANGELOG.md#190-2023-07-05)

[Compare Source](rust-lang/regex@1.8.4...1.9.0)

\==================
This release marks the end of a [years long rewrite of the regex crate
internals](rust-lang/regex#656). Since this is
such a big release, please report any issues or regressions you find. We would
also love to hear about improvements as well.

In addition to many internal improvements that should hopefully result in
"my regex searches are faster," there have also been a few API additions:

-   A new `Captures::extract` method for quickly accessing the substrings
    that match each capture group in a regex.
-   A new inline flag, `R`, which enables CRLF mode. This makes `.` match any
    Unicode scalar value except for `\r` and `\n`, and also makes `(?m:^)` and
    `(?m:$)` match after and before both `\r` and `\n`, respectively, but never
    between a `\r` and `\n`.
-   `RegexBuilder::line_terminator` was added to further customize the line
    terminator used by `(?m:^)` and `(?m:$)` to be any arbitrary byte.
-   The `std` Cargo feature is now actually optional. That is, the `regex` crate
    can be used without the standard library.
-   Because `regex 1.9` may make binary size and compile times even worse, a
    new experimental crate called `regex-lite` has been published. It prioritizes
    binary size and compile times over functionality (like Unicode) and
    performance. It shares no code with the `regex` crate.

New features:

-   [FEATURE #&#8203;244](rust-lang/regex#244):
    One can opt into CRLF mode via the `R` flag.
    e.g., `(?mR:$)` matches just before `\r\n`.
-   [FEATURE #&#8203;259](rust-lang/regex#259):
    Multi-pattern searches with offsets can be done with `regex-automata 0.3`.
-   [FEATURE #&#8203;476](rust-lang/regex#476):
    `std` is now an optional feature. `regex` may be used with only `alloc`.
-   [FEATURE #&#8203;644](rust-lang/regex#644):
    `RegexBuilder::line_terminator` configures how `(?m:^)` and `(?m:$)` behave.
-   [FEATURE #&#8203;675](rust-lang/regex#675):
    Anchored search APIs are now available in `regex-automata 0.3`.
-   [FEATURE #&#8203;824](rust-lang/regex#824):
    Add new `Captures::extract` method for easier capture group access.
-   [FEATURE #&#8203;961](rust-lang/regex#961):
    Add `regex-lite` crate with smaller binary sizes and faster compile times.
-   [FEATURE #&#8203;1022](rust-lang/regex#1022):
    Add `TryFrom` implementations for the `Regex` type.

Performance improvements:

-   [PERF #&#8203;68](rust-lang/regex#68):
    Added a one-pass DFA engine for faster capture group matching.
-   [PERF #&#8203;510](rust-lang/regex#510):
    Inner literals are now used to accelerate searches, e.g., `\w+@&#8203;\w+` will scan
    for `@`.
-   [PERF #&#8203;787](rust-lang/regex#787),
    [PERF #&#8203;891](rust-lang/regex#891):
    Makes literal optimizations apply to regexes of the form `\b(foo|bar|quux)\b`.

(There are many more performance improvements as well, but not all of them have
specific issues devoted to them.)

Bug fixes:

-   [BUG #&#8203;429](rust-lang/regex#429):
    Fix matching bugs related to `\B` and inconsistencies across internal engines.
-   [BUG #&#8203;517](rust-lang/regex#517):
    Fix matching bug with capture groups.
-   [BUG #&#8203;579](rust-lang/regex#579):
    Fix matching bug with word boundaries.
-   [BUG #&#8203;779](rust-lang/regex#779):
    Fix bug where some regexes like `(re)+` were not equivalent to `(re)(re)*`.
-   [BUG #&#8203;850](rust-lang/regex#850):
    Fix matching bug inconsistency between NFA and DFA engines.
-   [BUG #&#8203;921](rust-lang/regex#921):
    Fix matching bug where literal extraction got confused by `$`.
-   [BUG #&#8203;976](rust-lang/regex#976):
    Add documentation to replacement routines about dealing with fallibility.
-   [BUG #&#8203;1002](rust-lang/regex#1002):
    Use corpus rejection in fuzz testing.

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update again.

---

 - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check this box

---

This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiIzNi4wLjAiLCJ1cGRhdGVkSW5WZXIiOiIzNi44LjExIiwidGFyZ2V0QnJhbmNoIjoiZGV2ZWxvcCJ9-->

Co-authored-by: cabr2-bot <[email protected]>
Co-authored-by: crapStone <[email protected]>
Reviewed-on: https://codeberg.org/Calciumdibromid/CaBr2/pulls/1957
Reviewed-by: crapStone <[email protected]>
Co-authored-by: Calciumdibromid Bot <[email protected]>
Co-committed-by: Calciumdibromid Bot <[email protected]>
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