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Diffstat (limited to 'doc/global.n')
| -rw-r--r-- | doc/global.n | 47 |
1 files changed, 33 insertions, 14 deletions
diff --git a/doc/global.n b/doc/global.n index 2b8787a..34db146 100644 --- a/doc/global.n +++ b/doc/global.n @@ -5,10 +5,8 @@ '\" See the file "license.terms" for information on usage and redistribution '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. '\" -'\" RCS: @(#) $Id: global.n,v 1.3 2000/11/21 15:56:21 dkf Exp $ -'\" -.so man.macros .TH global n "" Tcl "Tcl Built-In Commands" +.so man.macros .BS '\" Note: do not modify the .SH NAME line immediately below! .SH NAME @@ -19,18 +17,39 @@ global \- Access global variables .SH DESCRIPTION .PP -This command is ignored unless a Tcl procedure is being interpreted. -If so then it declares the given \fIvarname\fR's to be global variables -rather than local ones. -Global variables are variables in the global namespace. -For the duration of the current procedure -(and only while executing in the current procedure), -any reference to any of the \fIvarname\fRs -will refer to the global variable by the same name. +This command has no effect unless executed in the context of a proc body. +If the \fBglobal\fR command is executed in the context of a proc body, it +creates local variables linked to the corresponding global variables (though +these linked variables, like those created by \fBupvar\fR, are not included +in the list returned by \fBinfo locals\fR). +.PP +If \fIvarname\fR contains namespace qualifiers, the local variable's name is +the unqualified name of the global variable, as determined by the +\fBnamespace tail\fR command. +.PP +\fIvarname\fR is always treated as the name of a variable, not an +array element. An error is returned if the name looks like an array element, +such as \fBa(b)\fR. +.SH EXAMPLES +This procedure sets the namespace variable \fI::a::x\fR +.CS +proc reset {} { + \fBglobal\fR a::x + set x 0 +} +.CE .PP -Please note that this is done by creating local variables that are -linked to the global variables, and therefore that these variables -will be listed by \fBinfo locals\fR like all other local variables. +This procedure accumulates the strings passed to it in a global +buffer, separated by newlines. It is useful for situations when you +want to build a message piece-by-piece (as if with \fBputs\fR) but +send that full message in a single piece (e.g. over a connection +opened with \fBsocket\fR or as part of a counted HTTP response). +.CS +proc accum {string} { + \fBglobal\fR accumulator + append accumulator $string \en +} +.CE .SH "SEE ALSO" namespace(n), upvar(n), variable(n) |