General string quoting for TCL

Question

I\'m writing a utility (which happens to be in python) which is generating output in the form of a TCL script. Given some arbitrary string variable (not unicode) in the python,

Answer 1

You really only need 2 rules,

• Escape curly braces
• Wrap the output in curly braces

You don't need to worry about newlines, non printable characters etc. They are valid in a literal string, and TCL has excellent Unicode support.

set s { 
this is
a 
long 
string. I have $10 [10,000 cents] only curly braces \{ need \} to be escaped.
\t is not  a real tab, but '    ' is. "quoting somthing" :
{matchin` curly braces are okay, list = string in tcl}
}

Edit In light of your comment, you can do the following:

• escape [] {} and $
• wrap the whole output in set s [subst { $output } ]

The beauty of Tcl is it a has a very simple grammar. There are no other characters besides the 3 above needed to be escaped.

Edit 2 One last try.

If you pass subst some options, you will only need to escape \ and {}

set s [subst -nocommands -novariables { $output } ]

You would need to come up with a regex to convert non printable characters to their escaped codes however.

Good luck!