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diff --git a/tcl8.6/doc/for.n b/tcl8.6/doc/for.n deleted file mode 100644 index 9a3235f..0000000 --- a/tcl8.6/doc/for.n +++ /dev/null @@ -1,87 +0,0 @@ -'\" -'\" Copyright (c) 1993 The Regents of the University of California. -'\" Copyright (c) 1994-1997 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 for n "" Tcl "Tcl Built-In Commands" -.so man.macros -.BS -'\" Note: do not modify the .SH NAME line immediately below! -.SH NAME -for \- 'For' loop -.SH SYNOPSIS -\fBfor \fIstart test next body\fR -.BE - -.SH DESCRIPTION -.PP -\fBFor\fR is a looping command, similar in structure to the C -\fBfor\fR statement. The \fIstart\fR, \fInext\fR, and -\fIbody\fR arguments must be Tcl command strings, and \fItest\fR -is an expression string. -The \fBfor\fR command first invokes the Tcl interpreter to -execute \fIstart\fR. Then it repeatedly evaluates \fItest\fR as -an expression; if the result is non-zero it invokes the Tcl -interpreter on \fIbody\fR, then invokes the Tcl interpreter on \fInext\fR, -then repeats the loop. The command terminates when \fItest\fR evaluates -to 0. If a \fBcontinue\fR command is invoked within \fIbody\fR then -any remaining commands in the current execution of \fIbody\fR are skipped; -processing continues by invoking the Tcl interpreter on \fInext\fR, then -evaluating \fItest\fR, and so on. If a \fBbreak\fR command is invoked -within \fIbody\fR -or \fInext\fR, -then the \fBfor\fR command will -return immediately. -The operation of \fBbreak\fR and \fBcontinue\fR are similar to the -corresponding statements in C. -\fBFor\fR returns an empty string. -.PP -Note: \fItest\fR should almost always be enclosed in braces. If not, -variable substitutions will be made before the \fBfor\fR -command starts executing, which means that variable changes -made by the loop body will not be considered in the expression. -This is likely to result in an infinite loop. If \fItest\fR is -enclosed in braces, variable substitutions are delayed until the -expression is evaluated (before -each loop iteration), so changes in the variables will be visible. -See below for an example: -.SH EXAMPLES -.PP -Print a line for each of the integers from 0 to 9: -.PP -.CS -\fBfor\fR {set x 0} {$x<10} {incr x} { - puts "x is $x" -} -.CE -.PP -Either loop infinitely or not at all because the expression being -evaluated is actually the constant, or even generate an error! The -actual behaviour will depend on whether the variable \fIx\fR exists -before the \fBfor\fR command is run and whether its value is a value -that is less than or greater than/equal to ten, and this is because -the expression will be substituted before the \fBfor\fR command is -executed. -.PP -.CS -\fBfor\fR {set x 0} $x<10 {incr x} { - puts "x is $x" -} -.CE -.PP -Print out the powers of two from 1 to 1024: -.PP -.CS -\fBfor\fR {set x 1} {$x<=1024} {set x [expr {$x * 2}]} { - puts "x is $x" -} -.CE -.SH "SEE ALSO" -break(n), continue(n), foreach(n), while(n) -.SH KEYWORDS -boolean, for, iteration, loop -'\" Local Variables: -'\" mode: nroff -'\" End: |