---input---
echo ${a//[\"]/}

---tokens---
'echo'        Name.Builtin
' '           Text.Whitespace
'${'          Literal.String.Interpol
'a'           Name.Variable
'//['         Punctuation
'\\"'         Literal.String.Escape
']/'          Punctuation
'}'           Literal.String.Interpol
'\n'          Text.Whitespace