>You can make a string containing all three sets via concatenation, but you often cause yourself problems if the string with embedded string delimiters is later re-parsed (ie used in a macro-expansion or EVAL().) For me, the main reason I make frequent use of the square bracket pairing is the use of the ' and " in names and addresses that I may want to use with macro-expansion where the expanded string will need explicit delimiting.
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Me too. You're correct here, [] rarely used in names or addresses or other strings that are subject of search or something like this.