SysIII/usr/src/man/man1/efl.1

.TH EFL 1
.SH NAME
ef\&l \- Extended Fortran Language
.SH SYNOPSIS
.B ef\&l
[ options ]
[ files ]
.SH DESCRIPTION
.I Ef\&l\^
compiles a program written in the
.SM EFL
language into clean Fortran
on the standard output.
.I Ef\&l\^
provides the C-like control constructs of
.IR ratfor (1):
.RS
.TP
statement grouping with braces.
.TP
decision-making:
.BR if ,
.BR if - else ,
and
.BR select - case
(also known as
.BR switch - case );
.br
.BR while ,
.BR for ,
Fortran
.BR do ,
.BR repeat ,
and
.BR repeat " .\|.\|. " until
loops;
.br
multi-level
.B break
and
.BR next .
.RE
.PP
.SM EFL
has C-like data structures, e.g.:
.RS
.TP
struct
.nf
{
integer \|flags(3)
character(8) \|name
long \|real \|coords(2)
} \|table(100)
.fi
.RE
.PP
The language offers generic functions,
assignment operators
.RB ( += ,
.BR &= ,
etc.), and
sequentially evaluated logical operators
.RB ( &&
and
.BR \(bv\(bv\^ ).
There is a uniform input/output syntax:
.IP
write(6,x,y\f3:\fPf(7,2), \|do \|i=1,10 \|{ \|a(i,j),z\f3.\fPb(i) \|}\|)
.PP
.SM EFL
also provides
some syntactic ``sugar'':
.RS
.TP
free-form input:
multiple statements per line; automatic continuation;
statement label names (not just numbers).
.TP
comments:
.B #
this is a comment.
.TP
translation of relational and logical operators:
.BR > ,
.BR >= ,
.BR & ,
etc., become
.BR \&.\s-1GT\s+1. ,
.BR \&.\s-1GE\s+1. ,
.BR \&.\s-1AND\s+1. ,
etc.
.TP
return expression to caller from function:
.BI "return (" expression )\fR
.TP
defines:
.br
.B define
.I name replacement\^
.TP
includes:
.br
.B include
.I file\^
.RE
.PP
.I Efl\^
understands several option arguments:
.B \-w
suppresses warning messages,
.B \-#
suppresses comments in the generated program,
and the default option
.B \-C
causes comments to be included in the generated program.
.PP
An argument with an embedded
.B =
(equal sign)
sets an
.SM EFL
option
as if it had appeared in an
.B option
statement at the start of the program.
Many options are described in the reference manual.
A set of defaults for a particular target machine may be selected
by one of the choices:
.BR "system=unix" ,
.BR "system=gcos" ,
or
.BR "system=cray" .
The default setting of the
.B system
option is the same as the machine the compiler is running on.
Other specific options determine the style of input/output,
error handling, continuation conventions, the number of characters packed
per word, and default formats.
.PP
.I Ef\&l\^
is best used with
.IR f77 (1).
.SH SEE ALSO
cc(1),
f77(1),
ratfor(1).
.br
.I "The Programming Language \s-1EFL\s+1\^"
by S.I. Feldman.