# Parameter pattern matching

**URL:** <https://forum.elixirforum.com/t/parameter-pattern-matching/14173>\
**Category:** Questions\
**Tags:** pattern-matching, function-clause\
**Created:** [May 12, 2018, 1:25pm UTC](https://forum.elixirforum.com/t/parameter-pattern-matching/14173 "2018-05-12T13:25:11Z")\
**Posts on this page:** 1\
**Showing post:** 8

<div class="post-metadata">

**Author:** ![dom](https://forum.elixirforum.com/user_avatar/forum.elixirforum.com/dom/32/9313_2.png) [@dom](https://forum.elixirforum.com/u/dom)\
**Post date:** [May 12, 2018, 4:42pm UTC](https://forum.elixirforum.com/t/parameter-pattern-matching/14173/8 "2018-05-12T16:42:22Z")

</div>

During compilation

```
def equal(a,a), do: true

```

is basically rewritten to

```
def equal(a,b) when a === b, do: true

```

Both these functions compile to the exact same bytecode.

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