case - Evaluate one of several scripts, depending on a given value
case string ?
in?
patList body ?
patList body
...?
case string ?
in? {
patList body ?
patList body
...?}
Note: the case command is obsolete and is supported only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 cases.
switch(3tcl)
case, match, regular expression