case(n) Tcl Built-In Commands case(n)_________________________________________________________________NAMEcase - Evaluate one of several scripts, depending on a
given value
SYNOPSIScase string ?in? patList body ?patList body ...?
case string ?in? {patList body ?patList body ...?}
_________________________________________________________________DESCRIPTION
Note: the case command is obsolete and is supported only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 argu-
ments. The first uses a separate argument for each of the
patterns and commands; this form is convenient if substi-
tutions 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.
KEYWORDS
case, match, regular expression
Tcl 7.0 1