Created SC2313 (markdown)

SC2313.md

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+## Quote array indices to avoid them expanding as globs.
+
+### Problematic code:
+
+```sh
+read -r foo[index]
+```
+
+### Correct code:
+
+```sh
+read -r "foo[index]"
+```
+
+### Rationale:
+
+ShellCheck found an array element passed to read, where the `[]` was not quoted. This means the array index `[index]` will be treated as a glob range, and the word may be replaced or trigger `failglob`.  
+
+In the problematic example, having a directory named `food` will cause the command to become `read -r food` instead, since `food` matches the glob `foo[index]`. The result is assigning a value to the wrong variable.
+
+Quote or escape the pattern as shown to ensure it always reads into the array `foo` at index `index`. 
+
+### Exceptions:
+
+None.
+
+### Related resources:
+
+* Help by adding links to BashFAQ, StackOverflow, man pages, POSIX, etc!