Created SC2184 (markdown)

SC2184.md

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+## Quote arguments to unset so they're not glob expanded.
+
+### Problematic code:
+
+```sh
+unset foo[index]
+```
+
+### Correct code:
+
+```sh
+unset 'foo[index]'
+```
+### Rationale:
+
+Arguments to `unset` are subject to regular glob expansion. This is especially relevant when unsetting indices in arrays, where `[..]` is considered a glob character group.
+
+In the problematic code, having a file called `food` in the current directory will result in `unset foo[index]` expanding to `unset food`, which will silently succeed without unsetting the element.
+
+Quoting so that the `[..]` is passed literally to `unset` solves the issue.
+
+### Exceptions:
+
+None.