'''[TIP] [http://www.tcl.tk/cgi-bin/tct/tip/323.html%|%#323: Do Nothing Gracefully]''', 
by [Colin McCormack], [Donald Porter], and [Kevin Kenny], and implemented 
in [Changes in Tcl/Tk 8.6%|%Tcl version 8.6], provides the rationale for commands 
that do nothing under certain circumstances.



** Description **

With the advent of the `[{*}]` operator which expands an empty [list] into nothing at all, 
it became clear that it would be useful in various cases if commands 
that normally accept variable number of arguments at the end of the command 
could handle the case of no arguments at all being passed. <<br>>
The TIP modified the following commands:

   `[file delete]`:   Accept zero pathnames.

   `[file mkdir]`:   Accept zero directories.

   `[global]`:   Accept zero [variable] names.

   `[glob]`:   Accept zero patterns and return a `no matches` error, or when '''`-nocomplain`''' is provided, [return] a [list] of zero matching files.

   `[lassign]`:   Accept zero variable names [http://core.tcl.tk/tcl/tktview/1671880fffffffffffff].

   `[linsert]`:   Accpet zero elements [http://core.tcl.tk/tcl/tktview/1672056fffffffffffff].

   `[lrepeat]`:   Accept both a ''number'' of `0`, and zero elements [http://core.tcl.tk/tcl/tktview/1671951fffffffffffff].

   `[my%|%my variable]`:   Accept zero variable names.

   `[namespace upvar]`:   Accept zero variable names

   `[tcl::tm::path%|%::tcl::tm::path] add`:   Accept zero paths.

   `[tcl::tm::path%|%::tcl::tm::path::remove]`:   Accept zero paths.

   `[variable]`:   Accept zero variable names [http://core.tcl.tk/tcl/tktview/1881284fffffffffffff].

   


<<categories>> TIP | {*}