Created SC2082 (markdown)

SC2082.md

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+## To expand via indirection, use name="foo$n"; echo "${!name}".
+
+### Problematic code:
+
+    var_1="hello world"
+    n=1
+    echo "${var_$n}"
+
+### Correct code:
+
+    var_1="hello world"
+    n=1
+    name="var_$n"
+    echo "${!name}"
+
+### Rationale:
+
+You can expand a variable `var_1` with `${var_1}`, but you can not generate the string `var_1` with an embedded expansion, like `var_$n`. Instead, you have to use an indirect reference.
+
+You can do this by creating a variable containing the variable name you want, e.g. `myvar="var_$n"` and then expanding it indirectly with `${!myvar}`. This will give the contents of the variable `var_1`. 
+
+### Exceptions:
+
+None