Lexical Analysis: Hard Parts

How does one do lexical analysis (tokenization) of Bash/Perl style string, where insertion in the middle is possible?
Say we have
print "Now is {get "time of day"} of {get "current date"}..."
print 'have a nice day!'
And {…} inserts value in the middle of a string.

How Lexer would know which double-quote closes the string and which is part of the string?

Python uses format-like routines, because parsing such strings is hard.

>>3
Are you implying that's not ugly? It looks like a corrupted Common Lisp file. Rewrite it in Lisp so I can actually read it.

Also
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