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Diffstat (limited to 'doc/proc.n')
| -rw-r--r-- | doc/proc.n | 194 |
1 files changed, 97 insertions, 97 deletions
@@ -1,97 +1,97 @@ -'\" -'\" Copyright (c) 1993 The Regents of the University of California. -'\" Copyright (c) 1994-1996 Sun Microsystems, Inc. -'\" -'\" See the file "license.terms" for information on usage and redistribution -'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. -'\" -'\" RCS: @(#) $Id: proc.n,v 1.5 2004/10/27 14:24:37 dkf Exp $ -'\" -.so man.macros -.TH proc n "" Tcl "Tcl Built-In Commands" -.BS -'\" Note: do not modify the .SH NAME line immediately below! -.SH NAME -proc \- Create a Tcl procedure -.SH SYNOPSIS -\fBproc \fIname args body\fR -.BE - -.SH DESCRIPTION -.PP -The \fBproc\fR command creates a new Tcl procedure named -\fIname\fR, replacing -any existing command or procedure there may have been by that name. -Whenever the new command is invoked, the contents of \fIbody\fR will -be executed by the Tcl interpreter. -Normally, \fIname\fR is unqualified -(does not include the names of any containing namespaces), -and the new procedure is created in the current namespace. -If \fIname\fR includes any namespace qualifiers, -the procedure is created in the specified namespace. -\fIArgs\fR specifies the formal arguments to the -procedure. It consists of a list, possibly empty, each of whose -elements specifies -one argument. Each argument specifier is also a list with either -one or two fields. If there is only a single field in the specifier -then it is the name of the argument; if there are two fields, then -the first is the argument name and the second is its default value. -.PP -When \fIname\fR is invoked a local variable -will be created for each of the formal arguments to the procedure; its -value will be the value of corresponding argument in the invoking command -or the argument's default value. -Arguments with default values need not be -specified in a procedure invocation. However, there must be enough -actual arguments for all the -formal arguments that don't have defaults, and there must not be any extra -actual arguments. There is one special case to permit procedures with -variable numbers of arguments. If the last formal argument has the name -\fBargs\fR, then a call to the procedure may contain more actual arguments -than the procedure has formals. In this case, all of the actual arguments -starting at the one that would be assigned to \fBargs\fR are combined into -a list (as if the \fBlist\fR command had been used); this combined value -is assigned to the local variable \fBargs\fR. -.PP -When \fIbody\fR is being executed, variable names normally refer to -local variables, which are created automatically when referenced and -deleted when the procedure returns. One local variable is automatically -created for each of the procedure's arguments. -Global variables can only be accessed by invoking -the \fBglobal\fR command or the \fBupvar\fR command. -Namespace variables can only be accessed by invoking -the \fBvariable\fR command or the \fBupvar\fR command. -.PP -The \fBproc\fR command returns an empty string. When a procedure is -invoked, the procedure's return value is the value specified in a -\fBreturn\fR command. If the procedure doesn't execute an explicit -\fBreturn\fR, then its return value is the value of the last command -executed in the procedure's body. -If an error occurs while executing the procedure -body, then the procedure-as-a-whole will return that same error. -.SH EXAMPLES -This is a procedure that accepts arbitrarily many arguments and prints -them out, one by one. -.CS -\fBproc\fR printArguments args { - foreach arg $args { - puts $arg - } -} -.CE -.PP -This procedure is a bit like the \fBincr\fR command, except it -multiplies the contents of the named variable by the value, which -defaults to \fB2\fR: -.CS -\fBproc\fR mult {varName {multiplier 2}} { - upvar 1 $varName var - set var [expr {$var * $multiplier}] -} -.CE - -.SH "SEE ALSO" -info(n), unknown(n) - -.SH KEYWORDS -argument, procedure +'\"
+'\" Copyright (c) 1993 The Regents of the University of California.
+'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
+'\"
+'\" See the file "license.terms" for information on usage and redistribution
+'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+'\"
+'\" RCS: @(#) $Id: proc.n,v 1.6 2007/10/29 01:42:19 dkf Exp $
+'\"
+.so man.macros
+.TH proc n "" Tcl "Tcl Built-In Commands"
+.BS
+'\" Note: do not modify the .SH NAME line immediately below!
+.SH NAME
+proc \- Create a Tcl procedure
+.SH SYNOPSIS
+\fBproc \fIname args body\fR
+.BE
+
+.SH DESCRIPTION
+.PP
+The \fBproc\fR command creates a new Tcl procedure named
+\fIname\fR, replacing
+any existing command or procedure there may have been by that name.
+Whenever the new command is invoked, the contents of \fIbody\fR will
+be executed by the Tcl interpreter.
+Normally, \fIname\fR is unqualified
+(does not include the names of any containing namespaces),
+and the new procedure is created in the current namespace.
+If \fIname\fR includes any namespace qualifiers,
+the procedure is created in the specified namespace.
+\fIArgs\fR specifies the formal arguments to the
+procedure. It consists of a list, possibly empty, each of whose
+elements specifies
+one argument. Each argument specifier is also a list with either
+one or two fields. If there is only a single field in the specifier
+then it is the name of the argument; if there are two fields, then
+the first is the argument name and the second is its default value.
+.PP
+When \fIname\fR is invoked a local variable
+will be created for each of the formal arguments to the procedure; its
+value will be the value of corresponding argument in the invoking command
+or the argument's default value.
+Arguments with default values need not be
+specified in a procedure invocation. However, there must be enough
+actual arguments for all the
+formal arguments that do not have defaults, and there must not be any extra
+actual arguments. There is one special case to permit procedures with
+variable numbers of arguments. If the last formal argument has the name
+\fBargs\fR, then a call to the procedure may contain more actual arguments
+than the procedure has formals. In this case, all of the actual arguments
+starting at the one that would be assigned to \fBargs\fR are combined into
+a list (as if the \fBlist\fR command had been used); this combined value
+is assigned to the local variable \fBargs\fR.
+.PP
+When \fIbody\fR is being executed, variable names normally refer to
+local variables, which are created automatically when referenced and
+deleted when the procedure returns. One local variable is automatically
+created for each of the procedure's arguments.
+Global variables can only be accessed by invoking
+the \fBglobal\fR command or the \fBupvar\fR command.
+Namespace variables can only be accessed by invoking
+the \fBvariable\fR command or the \fBupvar\fR command.
+.PP
+The \fBproc\fR command returns an empty string. When a procedure is
+invoked, the procedure's return value is the value specified in a
+\fBreturn\fR command. If the procedure does not execute an explicit
+\fBreturn\fR, then its return value is the value of the last command
+executed in the procedure's body.
+If an error occurs while executing the procedure
+body, then the procedure-as-a-whole will return that same error.
+.SH EXAMPLES
+This is a procedure that accepts arbitrarily many arguments and prints
+them out, one by one.
+.CS
+\fBproc\fR printArguments args {
+ foreach arg $args {
+ puts $arg
+ }
+}
+.CE
+.PP
+This procedure is a bit like the \fBincr\fR command, except it
+multiplies the contents of the named variable by the value, which
+defaults to \fB2\fR:
+.CS
+\fBproc\fR mult {varName {multiplier 2}} {
+ upvar 1 $varName var
+ set var [expr {$var * $multiplier}]
+}
+.CE
+
+.SH "SEE ALSO"
+info(n), unknown(n)
+
+.SH KEYWORDS
+argument, procedure
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