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remove is_match free function #165

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BurntSushi opened this issue Feb 15, 2016 · 1 comment
Closed

remove is_match free function #165

BurntSushi opened this issue Feb 15, 2016 · 1 comment
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1.0

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@BurntSushi
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I think it was unwise to ever add this and I didn't give much thought to it. I saw it as a convenience for just quickly matching a regex against some text, but:

  1. It's more explicit to just create the Regex value and us that to match.
  2. It encourages compiling the regex every time it's used to search text, which is an anti-pattern because compilation is much slower relative to execution.
@BurntSushi BurntSushi added this to the 1.0 milestone Feb 15, 2016
BurntSushi added a commit that referenced this issue May 7, 2016
@BurntSushi
Remove free is_match function.
7392c4e 
It encourages compiling a regex for every use, which can be convenient
in some circumstances but deadly for performance.

Fixes #165
BurntSushi added a commit that referenced this issue May 18, 2016
@BurntSushi
Remove free is_match function.
1344d17 
It encourages compiling a regex for every use, which can be convenient
in some circumstances but deadly for performance.

Fixes #165
BurntSushi added a commit that referenced this issue Aug 5, 2016
@BurntSushi
Remove free is_match function.
a0498db 
It encourages compiling a regex for every use, which can be convenient
in some circumstances but deadly for performance.

Fixes #165
@kevincox
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While I see the benefit of the function, the full API is so simple to use that it has little benefit and as you mentioned it encourages bad usage patterns. I don't feel strongly either way.

@BurntSushi BurntSushi mentioned this issue Dec 31, 2016
Merged
bors added a commit that referenced this issue Dec 31, 2016
@bors
Auto merge of #310 - BurntSushi:rfc, r=BurntSushi
52fdae7 
regex 0.2

0.2.0
=====
This is a new major release of the regex crate, and is an implementation of the
[regex 1.0 RFC](https://github.com/rust-lang/rfcs/blob/master/text/1620-regex-1.0.md).
We are releasing a `0.2` first, and if there are no major problems, we will
release a `1.0` shortly. For `0.2`, the minimum *supported* Rust version is
1.12.

There are a number of **breaking changes** in `0.2`. They are split into two
types. The first type correspond to breaking changes in regular expression
syntax. The second type correspond to breaking changes in the API.

Breaking changes for regex syntax:

* POSIX character classes now require double bracketing. Previously, the regex
  `[:upper:]` would parse as the `upper` POSIX character class. Now it parses
  as the character class containing the characters `:upper:`. The fix to this
  change is to use `[[:upper:]]` instead. Note that variants like
  `[[:upper:][:blank:]]` continue to work.
* The character `[` must always be escaped inside a character class.
* The characters `&`, `-` and `~` must be escaped if any one of them are
  repeated consecutively. For example, `[&]`, `[\&]`, `[\&\&]`, `[&-&]` are all
  equivalent while `[&&]` is illegal. (The motivation for this and the prior
  change is to provide a backwards compatible path for adding character class
  set notation.)
* A `bytes::Regex` now has Unicode mode enabled by default (like the main
  `Regex` type). This means regexes compiled with `bytes::Regex::new` that
  don't have the Unicode flag set should add `(?-u)` to recover the original
  behavior.

Breaking changes for the regex API:

* `find` and `find_iter` now **return `Match` values instead of
  `(usize, usize)`.** `Match` values have `start` and `end` methods, which
  return the match offsets. `Match` values also have an `as_str` method,
  which returns the text of the match itself.
* The `Captures` type now only provides a single iterator over all capturing
  matches, which should replace uses of `iter` and `iter_pos`. Uses of
  `iter_named` should use the `capture_names` method on `Regex`.
* The `replace` methods now return `Cow` values. The `Cow::Borrowed` variant
  is returned when no replacements are made.
* The `Replacer` trait has been completely overhauled. This should only
  impact clients that implement this trait explicitly. Standard uses of
  the `replace` methods should continue to work unchanged.
* The `quote` free function has been renamed to `escape`.
* The `Regex::with_size_limit` method has been removed. It is replaced by
  `RegexBuilder::size_limit`.
* The `RegexBuilder` type has switched from owned `self` method receivers to
  `&mut self` method receivers. Most uses will continue to work unchanged, but
  some code may require naming an intermediate variable to hold the builder.
* The free `is_match` function has been removed. It is replaced by compiling
  a `Regex` and calling its `is_match` method.
* The `PartialEq` and `Eq` impls on `Regex` have been dropped. If you relied
  on these impls, the fix is to define a wrapper type around `Regex`, impl
  `Deref` on it and provide the necessary impls.
* The `is_empty` method on `Captures` has been removed. This always returns
  `false`, so its use is superfluous.
* The `Syntax` variant of the `Error` type now contains a string instead of
  a `regex_syntax::Error`. If you were examining syntax errors more closely,
  you'll need to explicitly use the `regex_syntax` crate to re-parse the regex.
* The `InvalidSet` variant of the `Error` type has been removed since it is
  no longer used.
* Most of the iterator types have been renamed to match conventions. If you
  were using these iterator types explicitly, please consult the documentation
  for its new name. For example, `RegexSplits` has been renamed to `Split`.

A number of bugs have been fixed:

* [BUG #151](#151):
  The `Replacer` trait has been changed to permit the caller to control
  allocation.
* [BUG #165](#165):
  Remove the free `is_match` function.
* [BUG #166](#166):
  Expose more knobs (available in `0.1`) and remove `with_size_limit`.
* [BUG #168](#168):
  Iterators produced by `Captures` now have the correct lifetime parameters.
* [BUG #175](#175):
  Fix a corner case in the parsing of POSIX character classes.
* [BUG #178](#178):
  Drop the `PartialEq` and `Eq` impls on `Regex`.
* [BUG #179](#179):
  Remove `is_empty` from `Captures` since it always returns false.
* [BUG #276](#276):
  Position of named capture can now be retrieved from a `Captures`.
* [BUG #296](#296):
  Remove winapi/kernel32-sys dependency on UNIX.
* [BUG #307](#307):
  Fix error on emscripten.
@bors bors closed this as completed in cfd887d Dec 31, 2016
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@BurntSushi @kevincox