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.TITLE FLEX - FLECS FORTRAN PREPROCESSOR
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FLEX
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FLEX - FLECS FORTRAN PREPROCESSOR
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^^ROUTINE NAME: FLEX\\
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^^PURPOSE:\\ ^THE ^^FLECS\\ TRANSLATOR (^^FORTRAN\\ ^LANGUAGE ^EXTENDED ^CONTROL
^STRUCTURE) PROVIDES EXTENSIONS TO THE ^^FORTRAN\\ LANGUAGE AND
A PREPROCESSOR THAT IS TRANSPORTABLE FOR IMPLEMENTING THE
EXTENSIONS.
^^FLECS\\ CONTAINS NINE CONTROL STRUCTURES NOT FOUND IN STANDARD
^^FORTRAN\\.
^IN ALL OTHER WAYS ^^FLECS\\ IS IDENTICAL TO ^^FORTRAN\\, AND IMBEDDED ^^FORTRAN\\ CODE IS PASSED THROUGH
THE PREPROCESSOR UNCHANGED.
^THE ^^FLECS\\ PREPROCESSOR TRANSLATES ^^FLECS\\ CONTROL STRUCTURES
INTO EQUIVALENT ^^FORTRAN\\ AND PRODUCES A NICELY FORMATTED AND
INDENTED LISTING WHICH DISPLAYS THE LOGICAL STRUCTURE OF THE
PROGRAM.
^THE RESULT OF PREPROCESSING IS A LISTING AND A ^^FORTRAN\\ FILE READY
FOR COMPILATION WITH A STANDARD COMPILER.
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^^CALLABLE:\\ ^^FLEX\\ IS ^^MCR\\ CALLABLE WHEN INSTALLED AND ACCEPTS ^^MCR\\ COMMAND
LINES.
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^^PARAMETERS:\\ ^THE ^^MCR\\ COMMAND LINE INPUTS ARE:
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^^FORTRAN OUTPUT, FLECS FORMAT LISTING=FLECS FORMAT INPUT\\
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^THE DEFAULT EXTENSIONS ARE:
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^^.FTN, .FLL= .FLX\\
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^THE LISTING FILE IS SPOOLED AUTOMATICALLY.
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^^ROUTINES USED:\\ ^FOR BOTH ^^FOR\\ AND ^^F4P\\ THE LATEST VERSIONS WILL
COMPILE THE "^C" FORM OF THE COMPILER.
^THE ASSOCIATED ROUTINES, ^^FSUB & RSX\\, ARE COMPILED AND
ASSEMBLED, RESPECTIVELY, FOR INCLUSION IN THE TASK BUILD.
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^^EXAMPLE:\\ ^TO COMPILE A ^^FLECS\\ PROGRAM, THE FOLLOWING SEQUENCE IS USED:
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>^^FLEX PROG,PROG=PROG
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>FOR PROG,PROG/LI:0/SP=PROG\\  OR
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>^^F4P PROG,PROG/LI:0/SP=PROG\\
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^IT IS SELDOM NECESSARY TO USE THE ^^FORTRAN\\ LISTING IN PRACTICE
EXCEPT FOR ERRORS CAUGHT IN COMPILATION FOR WHICH LINE NUMBER 
MESSAGES HAVE NOT BEEN REQUESTED.
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^^FEATURES:\\ ^THE NINE CONTROL STRUCTURES ADDED TO ^^FORTRAN\\ ARE:
^^IF, UNLESS, WHEN...ELSE, CONDITIONAL, SELECT, DO, WHILE, UNTIL,
\\ AND ^^REPEAT\\.
^THE USE OF THESE STRUCTURES PERMITS THE ELIMINATION OF A DEPENDENCE
ON STATEMENT NUMBERS FOR CONTROL TRANSFER.
^AS FAR AS THE USER IS CONCERNED, THE CODE MAY BE WRITTEN USING THE
BEST OF STRUCTURED PROGRAMMING CONSTRAINTS AND MAY BE IN-LINE.
^FOR REPEATED FUNCTIONS OR FOR THE IMPLEMENTATION OF TOP-DOWN
DESIGN TECHNIQUES, INTERNAL PROCEDURES MAY BE DEFINED AND REFERENCED
WITH MEANINGFUL NAMES.
^THIS FACILITATES THE LAYOUT OF A DESIGN AND THE INCLUSING OF STUBS FOR
SECTIONS NOT YET INCLUDED.
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^^AUTHOR:\\ ^^FLECS\\ WAS WRITTEN BY ^TERRY ^BEYER OF THE ^UNIVERSITY OF ^OREGON
^COMPUTING ^CENTER.
^THE ASSEMBLY LANGUAGE SUPPORT ROUTINES FOR ^^RSX11\\ WERE WRITTEN BY
^CHRIS ^MEYERS OF THE ^EUGENE ^REGISTER ^GUARD IN ^EUGENE, ^OREGON.
^THE ROUTINES WERE MODIFIED BY ^GEORGE ^HAMMA OF THE ^LOCKHEED ^PALO
^ALTO ^RESEARCH ^LAB TO MATCH BOTH ^^FOR\\ AND ^^F4P\\ LINE-NUMBERING
SEQUENCES.
^THERE ARE TWO VERSIONS OF THE CODE, WITH CONDITIONAL ASSEMBLY USED TO
PICK THE DESIRED LINE-NUMBERING SEQUENCE.
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^^WRITTEN:\\ ^^FLECS\\ VERSION 22 WAS WRITTEN ON 10-^^SEP\\-74.
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^^SOURCE LANGUAGE:\\ ^^FLECS\\ IS WRITTEN IN ^^FLECS\\, BUT THE PROCESSED VERSION OF THE
CODE IS INCLUDED FOR THE INSTALLATION OF THE PREPROCESSOR USING
^^FORTRAN\\.
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^^OBJECT MODULE NAME:\\ ^^FLEX.OBJ, FSUB.OBJ, RSX.OBJ.
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^^LAST MODIFICATION:\\ ^THE MOST RECENT MODIFICATION TO THIS RELEASE WAS TO VERSION
22.37 DATED 7-^^MAR\\-77 BY ^GEORGE ^HAMMA.
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^^MAINTENANCE:\\ ^THE ^^FLECS\\ COMPILER IS MAINTAINED BY THE STAFF OF THE
^COMPUTING ^CENTER, ^UNIVERSITY OF ^OREGON, ^EUGENE,
^OREGON, 97403.
^THEIR PHONE NUMBER IS (503) 686-4416 AND THE
DISTRIBUTION IS HANDLED BY ^ALICE ^CHAN.
^^FLECS\\ IS IN THE PUBLIC DOMAIN.
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