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-
- Lexical Analyser Generator
-
- This is an implementation of the Unix program LEX, which generates
- lexical analysers from regular expression grammars. It was originally
- written by Charles Forsyth. It has been serially adapted as follows:
-
- Martin Minnow PDP-11 DECUS (DEC Users Society) C package
- Robert Denny RT-11, RSX, and VAX/VMS operating systems
- Scott Guthery DeSmet C on IBM PC/DOS
-
- Because the Decus C compiler does not seperate I and D space, LEX
- cannot be used to build very large grammars. There are several
- possibilities:
-
- 1. Remove the dfa/nfa print routines, which are needed
- for debugging.
-
- 2. Use I/O redirection to read the grammar source from
- stdin. This will save 1/4 K-word or so.
-
- 3. Overlay the parser phases.
-
- *** 3-Dec-80 ***
-
- I (Bob Denny) have overlaid things, after some reorganization, at least
- for RT-11. Also changed the allocation (static) for move vectors down to
- 1500. It easily processes the lex for C (CLEX.LXI), as the program top
- is at 17K or so.
-
- *** 7-Feb-81 ***
-
- Bob Denny...
- Increased the NFA's for RT-11 to 600, DFA's to 300. Now about 20K
-
- *** 28-May-81 ***
-
- Bob Denny...
- More fiddling with the allocations. Check out on RSX. This is how
- it's going into the DECUS library.
-
- *** 20-Nov-83 ***
-
- Scott Guthery...
- Removed VAX/VMS conditionals. Made up LEXDEFS.H for use by LEX (the old
- put the externals in a generally useful header file and then try to
- initialize 'em problem). Added some routines which were in Decus library
- but not in DeSmet library.
-
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-