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Diffstat (limited to 'pkg/language/doc/break.hlp')
-rw-r--r-- | pkg/language/doc/break.hlp | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/pkg/language/doc/break.hlp b/pkg/language/doc/break.hlp new file mode 100644 index 00000000..fce2cf9f --- /dev/null +++ b/pkg/language/doc/break.hlp @@ -0,0 +1,49 @@ +.help break Feb86 language +.ih +NAME +break -- break out of a loop +.ih +USAGE +break +.ih +DESCRIPTION +The \fIbreak\fR statement is used to exit (break out of) the \fIfor\fR or +\fIwhile\fR loop in which it is found. In the case of nested loop constructs +only the innermost loop is terminated. +Unlike C usage the \fIbreak\fR statement does not break out of a switch. +.ih +EXAMPLES +1. Scan a list (file), printing each list element until either the list is +exhausted or a list element "exit" or "quit" is encountered. + +.nf + while (fscan (list, s1) != EOF) { + if (s1 == "exit" || s1 == "quit") + break + print (s1) + } +.fi + + +2. Sum the pixels in a two dimensional array, terminating the sum for each +line if a negative pixel is encountered, and terminating the entire process +when the total sum passes a predefined limit. + +.nf + total = 0 + for (i=1; i <= NCOLS; i+=1) { + for (j=1; j <= NLINES; j+=1) { + if (pixel[i,j] < 0) + break # exit the J loop + total += pixel[i,j] + } + if (total > NPHOT) + break # exit the I loop + } +.fi +.ih +BUGS +.ih +SEE ALSO +next, while, for +.endhelp |