Name
flex
Synopsis
flex [options] [file]flex (Fast Lexical Analyzer Generator) is a faster variant of lex . It generates a lexical analysis program (named lex.yy.c) based on the regular expressions and C statements contained in one or more input files. See also bison, yacc, and the O’Reilly book lex & yacc.
Options
- -b
Generate backup information to lex.backup.
- -d
Debug mode.
- -f
Use faster compilation (limited to small programs).
- -h
Help summary.
- -i
Scan case-insensitively.
- -l
Maximum lex compatibility.
- -o file
Write output to file instead of lex.yy.c.
- -p
Print performance report.
- -s
Exit if the scanner encounters input that does not match any of its rules.
- -t
Print to standard output. (By default, flex prints to lex.yy.c.)
- -v
Print a summary of statistics.
- -w
Suppress warning messages.
- -B
Generate batch (noninteractive) scanner.
- -F
Use the fast scanner table representation.
- -I
Generate an interactive scanner (default).
- -L
Suppress #line directives in lex.yy.c.
- -P prefix
Change default yy prefix to prefix for all globally visible variable and function names.
- -V
Print version number.
- -7
Generate a 7-bit scanner.
- -8
Generate an 8-bit scanner (default).
- -+
Generate a C++ scanner class.
- -C
Compress scanner tables but do not use equivalence classes.
- -Ca
Align tables for memory access and computation. This creates larger tables but gives faster performance.
- -Ce
Construct equivalence classes. This creates smaller tables and sacrifices little performance (default).
- -Cf
Generate full scanner ...
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