Re: misunderstaning of switch command

On 24/06/2025 10:23, Mark Summerfield wrote:

I have a switch command which is doing something I don't expect but I
don't understand what I've done wrong. In this example the default is
always executed but I expect the case before that to be executed.
      const UNCOMPRESSED U
     const ZLIB_COMPRESSED Z
     const SAME_AS_PREV =
     set filename somefile.txt
     set action "added"
     set kind Z
     switch $kind {
         $::SAME_AS_PREV { puts "unchanged \"$filename\"" }
         $::UNCOMPRESSED { puts "$action \"$filename\"" }
         $::ZLIB_COMPRESSED { puts "$action \"$filename\" (zlib
compressed)" }
         default { puts "!!!!!!!! UNEXPECTED !!!!!!!!" }
     }
 What am I doing wrong?

Switch allows for two different ways to specify the pattern/body pairs: As as a single argument or as individual arguments. If you want the patterns to be in variables (or consts) you may prefer the latter method. This can be written as:
switch $kind \
   $::SAME_AS_PREV {
     puts "unchanged \"$filename\""
} $::UNCOMPRESSED {
     puts "$action \"$filename\""
} $::ZLIB_COMPRESSED {
     puts "$action \"$filename\" (zlib compressed)"
} default {
     puts "!!!!!!!! UNEXPECTED !!!!!!!!"
}
Schelte.