eval $var=(a b)
eval "$var=(a b)"
Shells differ widely in how they handle unescaped parentheses in
eval foo=baris 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/escape the characters accordingly.
ShellCheck is a static analysis tool for shell scripts. This page is part of its documentation.