ondich (06/14/82)
Our v7 Lex is recognizing "^" as beginning of line in the rules section, but not in the definitions section. For example: name ^[a-zA-Z] %% {name} {action...} is not performing the action for lines beginning with a letter, but %% ^[a-zA-Z] {action...} is working fine. Though not disastrous (I can simply use the second form), this problem has led to some aesthetically unpleasant code. Is the problem typical? Is it a bug? Perhaps a feature? Any enlightenment would be appreciated. Thanks, Jeff Ondich ihps3!stolaf!ondich
lacasse@RAND-UNIX@sri-unix (07/29/82)
Date: Sunday, 27 Jun 1982 15:55-PDT Re: Our v7 Lex is recognizing "^" as beginning of line in the rules section, but not in the definitions section. Put (parenthesis) around your definition, viz: name (^[a-zA-Z]) %% {name} {action...} In fact, it is good practice to put parenthesis around all lex definitions if you wish to avoid this and other bugs. More serious are certain bugs surrounding the use of yyless, REJECT, and look-aheads, when more than one of these three act on the same piece of text. Lex can delete one character of input text. Also, ^text will not match at the beginning of the file. Would anyone who has debugged these please contact me. Mark LaCasse Rand Corporation 1700 Main Street Santa Monica, CA 90406 213/393-0411