4.3BSD - /usr/man/cat1/fp.0

FP(1)                                                                    FP(1)


NAME
       fp -  Functional Programming language compiler/interpreter

SYNOPSIS
       fp

DESCRIPTION
       Fp  is an interpreter/compiler that implements the applicative language
       proposed by John Backus.  It is written in FRANZ LISP.

       In a  functional programming language intent is expressed in  a  mathe‐
       matical style devoid of assignment statements and variables.  Functions
       compute by value only; there are no side-effects since  the result of a
       computation depends solely on the inputs.

       Fp  "programs"  consist of functional expressions - primitive and user-
       defined fp functions combined by functional forms.   These  forms  take
       functional  arguments  and return functional results.  For example, the
       composition operator ���@��� takes two functional arguments and  returns  a
       function which represents their composition.

       There  exists  a  single operation in fp - application.  This operation
       causes the system to evaluate the indicated function using  the  single
       argument as input (all functions are monadic).

GETTING STARTED
       Fp invokes the system.  Fp compiles functions into lisp(1) source code;
       lisp(1) interprets this code (the user may compile this code using  the
       liszt  (1)  compiler to gain a factor of 10 in performance).  Control D
       exits back to the shell.  Break terminates any computation in  progress
       and  resets any open file units.  )help provides a short summary of all
       user commands.

FILES
       /usr/ucb/lisp  the FRANZ LISP interpreter
       /usr/ucb/liszt the liszt compiler
       /usr/doc/fp    the User’s Guide

SEE ALSO
       lisp(1), liszt(1).

       The Berkeley FP user���s manual,  available  on-line.   The  language  is
       described   in   the August 1978 issue of CACM (Turing award lecture by
       John Backus).

BUGS
       If a non-terminating function is applied as the  result  of  loading  a
       file,  then  control  is  returned  to the user immediately, everything
       after that position in the file is ignored.

       FP incorrectly marks the location of a syntax error  on  large,  multi-
       line function definitions or applications.

AUTHOR
       Scott B. Baden


4.2 Berkeley Distribution       April 29, 1985                           FP(1)