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diff --git a/tcl8.6/doc/proc.n b/tcl8.6/doc/proc.n deleted file mode 100644 index fdccaca..0000000 --- a/tcl8.6/doc/proc.n +++ /dev/null @@ -1,128 +0,0 @@ -'\" -'\" 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. -'\" -.TH proc n "" Tcl "Tcl Built-In Commands" -.so man.macros -.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. -Arguments with default values that are followed by non-defaulted -arguments become required arguments; enough actual arguments must be -supplied to allow all arguments up to and including the last required -formal argument. -.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. -Actual arguments are assigned to formal arguments strictly in order. -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. -Arguments with default values that are followed by non-defaulted -arguments become de-facto required arguments, though this may change -in a future version of Tcl; portable code should ensure that all -optional arguments come after all required arguments. -.PP -There is one special case to permit procedures with -variable numbers of arguments. If the last formal argument has the name -.QW \fBargs\fR , -then a call to the procedure may contain more actual arguments -than the procedure has formal arguments. 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. -Other variables can only be accessed by invoking one of the \fBglobal\fR, -\fBvariable\fR, \fBupvar\fR or \fBnamespace upvar\fR commands. -The current namespace when \fIbody\fR is executed will be the -namespace that the procedure's name exists in, which will be the -namespace that it was created in unless it has been changed with -\fBrename\fR. -'\" We may change this! It makes [variable] unstable when renamed and is -'\" frankly pretty crazy, but doing it right is harder than it looks. -.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 -.PP -This is a procedure that takes two arguments and prints both their sum -and their product. It also returns the string -.QW OK -to the caller as an explicit result. -.PP -.CS -\fBproc\fR printSumProduct {x y} { - set sum [expr {$x + $y}] - set prod [expr {$x * $y}] - puts "sum is $sum, product is $prod" - return "OK" -} -.CE -.PP -This is a procedure that accepts arbitrarily many arguments and prints -them out, one by one. -.PP -.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: -.PP -.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 -'\" Local Variables: -'\" mode: nroff -'\" End: |