Specify that caught exceptions should be assigned to a variable named `$e` #4491

dantleech · 2014-11-19T08:45:18Z

320 out of 372 catches in the symfony code base use $e.

git grep "catch (.*Exception" | grep "\$e)" | wc -l                                                                                                                                               
320
git grep "catch (.*Exception" | wc -l
372

I think it would be good to make this a standard?

i.e.

try {
    // foo
} catch (SomeException $e) {
    // bar
}

as opposed to using variations: $ex (5 instances) $exception (2 instances), etc.

… `$e` 320 out of 372 catches use `$e`.

linaori · 2014-11-19T12:52:09Z

It's just a minor thing, but I think it will help a lot. One example could be where you have a kernel.exception event being fired, you do a fallback and you end up having 2 exception variables in the same method. There shouldn't be any confusion if you always use $e.

Nek- · 2014-11-19T13:04:21Z

👍

xabbuh · 2014-11-19T15:09:05Z

contributing/code/standards.rst

@@ -141,6 +141,8 @@ Naming Conventions

 * Don't forget to look at the more verbose :doc:`conventions` document for
  more subjective naming considerations.


This item should then end with a semicolon.

xabbuh · 2014-11-19T15:10:03Z

In my opinion this makes sense. But let's see what the rest (especially @symfony/deciders) think about this.

wouterj · 2014-11-19T15:19:29Z

-1

It doesn't add much value to standardize it
A catch block is often a very small block, it wouldn't be hard to find the correct variable name
Forcing it means having problems with nested try..catch blocks.
Forcing exact variable names is never a good thing imo, as it all depends on the context.

dantleech · 2014-11-19T15:27:59Z

But the standard should be $e, if somebody was writing

try {
   // foo
} catch (Exception $foobar) {
   // bar
}

That would be wrong

So would:

try {
    //
} catch (Exception $excep) {
   //
}

try {
} catch (Exception $ex) {
}

I think the standard should be $e, unless there is reason not to do this.

javiereguiluz · 2014-11-19T15:32:53Z

@wouterj your answer surprises me because you are always in for cleaning inconsistencies :) I think @dantleech has reported a hard to justify inconsistency: Symfony uses $e "almost always" ... why not make it just "always"?

linaori · 2014-11-19T15:37:18Z

I agree with @wouterj about dictating conventions for variables, but I also agree with @javiereguiluz. I think that we should make an exception for $e.

How many cases of nested exceptions are there in Symfony packages?
What would the recommended variable naming be there?

dantleech · 2014-11-24T19:11:14Z

I can find one, which uses $e2

https://github.com/symfony/symfony/blob/2.7/src/Symfony/Component/Routing/Matcher/RedirectableUrlMatcher.php#L40

using a very unconclusive search that assumes that nested try keywords are within the following five lines of the catch.

I would say that this should be a guideline. If you must have nested exceptions you should make an exception to the rule. It seems to happen rarely enough.

wouterj · 2015-02-19T23:38:12Z

@symfony/deciders what are your opinion on this proposed CS?

wouterj · 2015-05-17T15:48:34Z

ping @stof @fabpot @jakzal @weaverryan can you please share your opinion on this topic?

jakzal · 2015-05-17T18:18:48Z

👎 I would not put this into coding standards. It should be up to the author of code to give proper names so the code is readable, and that's not something you can standardise.

However, I'd vote 👍 if someone sent a PR to symfony/symfony fixing the inconsistency. Especially that there's only few instances that don't follow this pattern.

javiereguiluz · 2015-06-11T11:07:08Z

This pull request can be closed because doc managers and Symfony deciders are against it. Moreover, the idea proposed by @dantleech to update the exception variables to $e across the framework has been implemented in symfony/symfony#14937 and it's waiting for the Symfony deciders opinion. Thanks.

xabbuh · 2015-06-11T11:13:53Z

I agree. Though thanks to @dantleech for starting the discussion and to @javiereguiluz for updating the code.

…guiluz) This PR was squashed before being merged into the 2.3 branch (closes #14937). Discussion ---------- Standardize the name of the exception variables | Q | A | ------------- | --- | Bug fix? | no | New feature? | no | BC breaks? | no | Deprecations? | no | Tests pass? | yes | Fixed tickets | - | License | MIT | Doc PR | - See symfony/symfony-docs#4491 for the context of this change. In Symfony source code there are 410 `try ... catch` blocks. More than 95% of them use `$e` as the name of the exception variable. After applying these changes, 407 out of 410 variables are named `$e`. These are the three cases where I didn't change the name of the `$e` variable: * Nested exception in https://github.com/symfony/symfony/blob/2.3/src/Symfony/Component/Routing/Matcher/RedirectableUrlMatcher.php#L40. It uses `$e2` as the name of the nested variable. * Nested exception in https://github.com/symfony/symfony/blob/2.3/src/Symfony/Bundle/TwigBundle/TwigEngine.php#L82. I changed the name of the `$ex` variable to `$e2` to match the previous syntax. * https://github.com/symfony/symfony/blob/2.3/src/Symfony/Component/Console/Helper/DialogHelper.php#L463. I don't know if it's safe to change the name of the `$error` exception variable. Commits ------- e8b924c Standardize the name of the exception variables

…guiluz) This PR was squashed before being merged into the 2.3 branch (closes #14937). Discussion ---------- Standardize the name of the exception variables | Q | A | ------------- | --- | Bug fix? | no | New feature? | no | BC breaks? | no | Deprecations? | no | Tests pass? | yes | Fixed tickets | - | License | MIT | Doc PR | - See symfony/symfony-docs#4491 for the context of this change. In Symfony source code there are 410 `try ... catch` blocks. More than 95% of them use `$e` as the name of the exception variable. After applying these changes, 407 out of 410 variables are named `$e`. These are the three cases where I didn't change the name of the `$e` variable: * Nested exception in https://github.com/symfony/symfony/blob/2.3/src/Symfony/Component/Routing/Matcher/RedirectableUrlMatcher.php#L40. It uses `$e2` as the name of the nested variable. * Nested exception in https://github.com/symfony/symfony/blob/2.3/src/Symfony/Bundle/TwigBundle/TwigEngine.php#L82. I changed the name of the `$ex` variable to `$e2` to match the previous syntax. * https://github.com/symfony/symfony/blob/2.3/src/Symfony/Component/Console/Helper/DialogHelper.php#L463. I don't know if it's safe to change the name of the `$error` exception variable. Commits ------- e8b924c Standardize the name of the exception variables

…guiluz) This PR was squashed before being merged into the 2.3 branch (closes #14937). Discussion ---------- Standardize the name of the exception variables | Q | A | ------------- | --- | Bug fix? | no | New feature? | no | BC breaks? | no | Deprecations? | no | Tests pass? | yes | Fixed tickets | - | License | MIT | Doc PR | - See symfony/symfony-docs#4491 for the context of this change. In Symfony source code there are 410 `try ... catch` blocks. More than 95% of them use `$e` as the name of the exception variable. After applying these changes, 407 out of 410 variables are named `$e`. These are the three cases where I didn't change the name of the `$e` variable: * Nested exception in https://github.com/symfony/symfony/blob/2.3/src/Symfony/Component/Routing/Matcher/RedirectableUrlMatcher.php#L40. It uses `$e2` as the name of the nested variable. * Nested exception in https://github.com/symfony/symfony/blob/2.3/src/Symfony/Bundle/TwigBundle/TwigEngine.php#L82. I changed the name of the `$ex` variable to `$e2` to match the previous syntax. * https://github.com/symfony/symfony/blob/2.3/src/Symfony/Component/Console/Helper/DialogHelper.php#L463. I don't know if it's safe to change the name of the `$error` exception variable. Commits ------- e8b924c Standardize the name of the exception variables

…guiluz) This PR was squashed before being merged into the 2.3 branch (closes #14937). Discussion ---------- Standardize the name of the exception variables | Q | A | ------------- | --- | Bug fix? | no | New feature? | no | BC breaks? | no | Deprecations? | no | Tests pass? | yes | Fixed tickets | - | License | MIT | Doc PR | - See symfony/symfony-docs#4491 for the context of this change. In Symfony source code there are 410 `try ... catch` blocks. More than 95% of them use `$e` as the name of the exception variable. After applying these changes, 407 out of 410 variables are named `$e`. These are the three cases where I didn't change the name of the `$e` variable: * Nested exception in https://github.com/symfony/symfony/blob/2.3/src/Symfony/Component/Routing/Matcher/RedirectableUrlMatcher.php#L40. It uses `$e2` as the name of the nested variable. * Nested exception in https://github.com/symfony/symfony/blob/2.3/src/Symfony/Bundle/TwigBundle/TwigEngine.php#L82. I changed the name of the `$ex` variable to `$e2` to match the previous syntax. * https://github.com/symfony/symfony/blob/2.3/src/Symfony/Component/Console/Helper/DialogHelper.php#L463. I don't know if it's safe to change the name of the `$error` exception variable. Commits ------- e8b924c Standardize the name of the exception variables

Specify that caught exceptions should be assigned to a variable named…

5c8d586

… `$e` 320 out of 372 catches use `$e`.

xabbuh reviewed Nov 19, 2014
View reviewed changes

wouterj added Status: Needs Work needs comments labels Nov 23, 2014

dantleech mentioned this pull request Nov 24, 2014

Added reconnect to mysql sulu/sulu#597

Merged

javiereguiluz mentioned this pull request Jun 10, 2015

Standardize the name of the exception variables symfony/symfony#14937

Closed

xabbuh closed this Jun 11, 2015

javiereguiluz added Waiting feedback and removed Waiting feedback needs comments labels Jan 29, 2019

javiereguiluz removed the needs comments label Jan 29, 2019

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Specify that caught exceptions should be assigned to a variable named `$e` #4491

Specify that caught exceptions should be assigned to a variable named `$e` #4491

dantleech commented Nov 19, 2014

linaori commented Nov 19, 2014

Nek- commented Nov 19, 2014

xabbuh Nov 19, 2014

xabbuh commented Nov 19, 2014

wouterj commented Nov 19, 2014

dantleech commented Nov 19, 2014

javiereguiluz commented Nov 19, 2014

linaori commented Nov 19, 2014

dantleech commented Nov 24, 2014

wouterj commented Feb 19, 2015

wouterj commented May 17, 2015

jakzal commented May 17, 2015

javiereguiluz commented Jun 11, 2015

xabbuh commented Jun 11, 2015

		@@ -141,6 +141,8 @@ Naming Conventions

		* Don't forget to look at the more verbose :doc:`conventions` document for
		more subjective naming considerations.

Specify that caught exceptions should be assigned to a variable named $e #4491

Specify that caught exceptions should be assigned to a variable named $e #4491

Conversation

dantleech commented Nov 19, 2014

linaori commented Nov 19, 2014

Nek- commented Nov 19, 2014

xabbuh Nov 19, 2014

Choose a reason for hiding this comment

xabbuh commented Nov 19, 2014

wouterj commented Nov 19, 2014

dantleech commented Nov 19, 2014

javiereguiluz commented Nov 19, 2014

linaori commented Nov 19, 2014

dantleech commented Nov 24, 2014

wouterj commented Feb 19, 2015

wouterj commented May 17, 2015

jakzal commented May 17, 2015

javiereguiluz commented Jun 11, 2015

xabbuh commented Jun 11, 2015

Specify that caught exceptions should be assigned to a variable named `$e` #4491

Specify that caught exceptions should be assigned to a variable named `$e` #4491