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+## This is a unicode dash. Delete and retype as ASCII minus.
+
+### Problematic code:
+
+```sh
+[[ 3 –gt 2 ]] # Uses unicode en-dash character
+```
+
+### Correct code:
+
+```sh
+[[ 3 -gt 2 ]] # Uses regular ASCII hyphen-minus character
+```
+### Rationale:
+
+A character that looks similar to `-` has made its way into your code. This is usually due to copy-pasting from blogs and other websites that formatted code as text, replacing the ASCII hyphen-minus with a Unicode dash character.
+
+To fix it, simply delete and retype it.
+
+For a large script, you can use your editor's Search&Replace by copy-pasting the bad dash.
+
+### Exceptions:
+
+None. If you want a literal Unicode dash character, just quote it.
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