Note: the case command is obsolete and is supported only
for backward compatibility. At some point in the future it may be
removed entirely. You should use the switch command instead.
The case command matches string against each of
the patList arguments in order.
Each patList argument is a list of one or
more patterns. If any of these patterns matches string then
case evaluates the following body argument
by passing it recursively to the Tcl interpreter and returns the result
of that evaluation.
Each patList argument consists of a single
pattern or list of patterns. Each pattern may contain any of the wild-cards
described under string match. If a patList
argument is default, the corresponding body will be evaluated
if no patList matches string. If no patList argument
matches string and no default is given, then the case
command returns an empty string.
Two syntaxes are provided for the patList and body arguments.
The first uses a separate argument for each of the patterns and commands;
this form is convenient if substitutions are desired on some of the
patterns or commands.
The second form places all of the patterns and commands together into
a single argument; the argument must have proper list structure, with
the elements of the list being the patterns and commands.
The second form makes it easy to construct multi-line case commands,
since the braces around the whole list make it unnecessary to include a
backslash at the end of each line.
Since the patList arguments are in braces in the second form,
no command or variable substitutions are performed on them; this makes
the behavior of the second form different than the first form in some