| lex.1 (108470) | lex.1 (108533) |
|---|---|
| 1.\" $FreeBSD: head/usr.bin/lex/lex.1 108470 2002-12-30 21:18:15Z schweikh $ | 1.\" $FreeBSD: head/usr.bin/lex/lex.1 108533 2003-01-01 18:49:04Z schweikh $ |
| 2.\" 3.TH FLEX 1 "April 1995" "Version 2.5" 4.SH NAME 5flex \- fast lexical analyzer generator 6.SH SYNOPSIS 7.B flex 8.B [\-bcdfhilnpstvwBFILTV78+? \-C[aefFmr] \-ooutput \-Pprefix \-Sskeleton] 9.B [\-\-help \-\-version] --- 3117 unchanged lines hidden (view full) --- 3127.I we 3128know that there will never be any characters in the input stream 3129other than letters or newlines, 3130.I flex 3131can't figure this out, and it will plan for possibly needing to back up 3132when it has scanned a token like "auto" and then the next character 3133is something other than a newline or a letter. Previously it would 3134then just match the "auto" rule and be done, but now it has no "auto" | 2.\" 3.TH FLEX 1 "April 1995" "Version 2.5" 4.SH NAME 5flex \- fast lexical analyzer generator 6.SH SYNOPSIS 7.B flex 8.B [\-bcdfhilnpstvwBFILTV78+? \-C[aefFmr] \-ooutput \-Pprefix \-Sskeleton] 9.B [\-\-help \-\-version] --- 3117 unchanged lines hidden (view full) --- 3127.I we 3128know that there will never be any characters in the input stream 3129other than letters or newlines, 3130.I flex 3131can't figure this out, and it will plan for possibly needing to back up 3132when it has scanned a token like "auto" and then the next character 3133is something other than a newline or a letter. Previously it would 3134then just match the "auto" rule and be done, but now it has no "auto" |
| 3135rule, only a "auto\\n" rule. To eliminate the possibility of backing up, | 3135rule, only an "auto\\n" rule. To eliminate the possibility of backing up, |
| 3136we could either duplicate all rules but without final newlines, or, 3137since we never expect to encounter such an input and therefore don't 3138how it's classified, we can introduce one more catch-all rule, this 3139one which doesn't include a newline: 3140.nf 3141 3142 %% 3143 asm\\n | --- 925 unchanged lines hidden --- | 3136we could either duplicate all rules but without final newlines, or, 3137since we never expect to encounter such an input and therefore don't 3138how it's classified, we can introduce one more catch-all rule, this 3139one which doesn't include a newline: 3140.nf 3141 3142 %% 3143 asm\\n | --- 925 unchanged lines hidden --- |