info default procname arg varname
Procname must be the name of a Tcl procedure and arg must be the name of an argument to that procedure. If arg doesn't have a default value then the command returns 0. Otherwise it returns 1 and places the default value of arg into variable varname.
Zarutian 03. july 2005: why does this sub-procedure require an varname? It realy should return an list with two elements. The first one is the boolean (predicate: this arg of this proc has default value?). The second one is the default value (Empty if the boolean is "0" (false)).
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