Created SC1098 (markdown)

SC1098.md

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+## Quote/escape special characters when using eval, e.g. eval "a=(b)".
+
+### Problematic code:
+
+    eval $var=(a b)
+
+### Correct code:
+
+    eval "$var=(a b)"
+
+### Rationale:
+
+Shells differ widely in how they handle unescaped parentheses in `eval` expressions.
+
+* `eval foo=bar` is allowed by dash, bash and ksh.
+* `eval foo=(bar)` is allowed by bash and ksh, but not dash.
+* `eval $var=(bar)` is allowed by ksh, but not bash or dash.
+* `eval foo() ( echo bar; )` is not allowed by any shell.
+
+Since the expression is evaluated as shell script code anyways, it should be passed in as a literal string without relying on special case parsing rules in the target shell. Quote or escape the characters appropriately.
+
+### Exceptions:
+
+None.