From 44dbb5648b4a0bdf38a5161ca54173cfec6efeb5 Mon Sep 17 00:00:00 2001
From: koalaman <vidar@vidarholen.net>
Date: Sat, 31 Dec 2016 13:44:01 -0800
Subject: [PATCH] Created SC2200 (markdown)

---
 SC2200.md | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 SC2200.md

diff --git a/SC2200.md b/SC2200.md
new file mode 100644
index 0000000..81a14e1
--- /dev/null
+++ b/SC2200.md
@@ -0,0 +1,29 @@
+## Brace expansions don't work as operands in [ ]. Use a loop.
+
+### Problematic code:
+
+```sh
+[ "$file" = index.{htm,html,php} ] && echo "This is the main file"
+
+```
+
+### Correct code:
+
+```sh
+for main in index.{htm,html,php}
+do
+  [ "$file" = "$main" ] && echo "This is the main file"
+done
+```
+
+### Rationale:
+
+Brace expansions in `[ ]` will expand to a sequence of words. Operators work on single words.
+
+The problematic code is equivalent to `[ "$file" = index.htm index.html index.php ]`, which is invalid syntax. A typical error message is `bash: [: too many arguments` or `dash: somefile: unexpected operator`. 
+
+Instead, use a `for` loop to iterate over values, and apply your condition to each.
+
+### Exceptions:
+
+None.
\ No newline at end of file