Some common mistakes when programming in Tcl/Tk

Purpose: gather references and tips regarding common Tcl programming pitfalls

  1. Cameron Laird has created to document his version of Frequently Made Mistakes (FMM) in Tcl
  2. Is white space significant in Tcl? is another common question/problem.
  3. Quoting hell is another one
  4. Why can I not place unmatched braces in Tcl comments? is another of the common mistake/problems
  5. Recently in comp.lang.tcl, Darren New says: ... "You need to learn the difference between $address and address, and where each is appropriate.", then goes on to explain when one should use $variable_name and when one should use variable_name - some Tcl commands wants the name of a variable, while most want the value of a variable.
  6. Kevin Kenny declares: Update considered harmful
  7. Don't Do That! documents a variety of things that Tcl/Tk programmers should avoid doing.
  8. Tk image Dos and Don'ts documents a variety of image related things that Tk programmers should consider.
  9. Overinterpreting metacharacters: "" and {} are just for grouping - foo is "foo" is {foo}. Only at whitespaces and substitutions do they make a difference.
  10. Mike Hall writes in comp.lang.tcl "Never name your script file the same name as a widget class."
  11. AM A common mistake under UNIX/Linux: calling an executable (binary or script file) "test". This is not a Tcl problem - instead this item may not get executed since most command shells have an internal command "test" that is executed instead. However, if you use a full or partial path name (/path/to/test or ./test) it may work. Best approach is not to give it that name - just as you should not use the names of other built in commands (like cd, pwd, etc.)