Add Named Regex Captures Are Assigned To Variables as a ruby til

ruby/named-regex-captures-are-assigned-to-variables.md

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+# Named Regex Captures Are Assigned To Variables
+
+Both `String` and `Regexp` include the `=~` operator as a way of checking if a
+string and a regex match.
+
+When the `Regexp` version of
+[`=~`](https://ruby-doc.org/core-2.5.1/Regexp.html#method-i-3D~) with named
+capture groups, those named captures will be auto-assigned as local variables.
+
+Here is a regex that includes a named capture: `(?<id>\d+)`. The parentheses
+define the capture area and the `?<id>` specifies that whatever follows in the
+capture will be named `id`.
+
+```
+/Tile: (?<id>\d+)/ =~ 'Tile: 1234'
+#=> 0
+id
+=> "1234"
+```
+
+After the match operator (`=~`) runs in the first line, the local variable `id`
+gets assigned to whatever it matches in the corresponding string.
+
+[source](https://ruby-doc.org/core-2.5.1/Regexp.html#class-Regexp-label-Capturing)