This Tcl 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. <> Fair enough, but you can't erase this command from history. In fact the command is valid in current Tcl! Until recently there was a link to http://purl.org/tcl/home/man/tcl8.4/TclCmd/case.htm but that link is dead now. It would be fine if someone could restore this piece of documentation. [LV] For whatever reason, that file was deleted from www.tcl.tk . Perhaps all the deprecated commands were removed? I'm uncertain. ---- Suppose you have some old code using this command, and as a good Tcl citizen you want to follow the advice above. But how are you supposed to rewrite the line and use switch instead if there is no specification to be found of the old command? Note that it is not as simple as substituting "case" by "'switch"... ---- [RS] 2005-12-04 - Remember that Tcl has quite helpful error messages. I tried this: % case wrong # args: should be "case string ?in? patList body ... ?default body?" % case foo in {a* b*} {puts 1} {c* d*} {puts 2} {e* f*} {puts 3} 3 So it appears as if elements in ''patList'' are matched in [glob] style :) Compare this to the ''case'' control structure in Unix shells, e.g. in [bash]: case word in [ [(] pattern [ | pattern ] ... ) list ;; ] ... esac A case command first expands word, and tries to match it against each pattern in turn, using the same matching rules as for pathname expansion (see Pathname Expansion below). When a match is found, the corresponding list is executed. After the first match, no subsequent matches are attempted. The exit status is zero if no pattern matches. Otherwise, it is the exit status of the last com- mand executed in list. with the bad voodoo of using ";;" as case separator, and ''esac'' as end marker... ---- Bernard Desgraupes on the Alpha developers list kindly provided the man page, digged out from the 8.0.5 distribution: ===none NAME case - Evaluate one of several scripts, depending on a given value SYNOPSIS '''case''' ''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 '''{'''''patList body'' ?''patList body ...''?'''}''' DESCRIPTION Note: the '''case''' command is obsolete and is supported only for backward compatibility.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'' 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. KEYWORDS case, match, [regular expression] === <> Command