;;; GNU Guix --- Functional package management for GNU
  Copyright © 2012 , 2013 , 2014 , 2019   <  >
  Copyright © 2016   <  >
;;;
;;; This file is part of GNU Guix.
;;;
  GNU  is free software ; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by
  the Free Software Foundation ; either version 3 of the License , or ( at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;;; GNU General Public License for more details.
;;;
  You should have received a copy of the GNU General Public License
  along with GNU  .   If not , see < / > .

(define-module (gnu packages flex)
  #:use-module (guix licenses)
  #:use-module (guix packages)
  #:use-module (guix download)
  #:use-module (guix build-system gnu)
  #:use-module (guix utils)
  #:use-module (gnu packages)
  #:use-module (gnu packages m4)
  #:use-module (gnu packages man)
  #:use-module (gnu packages bison)
  #:use-module (srfi srfi-1))

(define-public flex
  (package
    (name "flex")
    (version "2.6.4")
    (source (origin
              (method url-fetch)
              (uri (string-append
                    ""
                    "/releases/download/v" version "/"
                    "flex-" version ".tar.gz"))
              (sha256
               (base32
                "15g9bv236nzi665p9ggqjlfn4dwck5835vf0bbw2cz7h5c1swyp8"))))
    (build-system gnu-build-system)
    (inputs
     (let ((bison-for-tests
            (package
              (inherit bison)
              (arguments
               ;; Disable tests, since they require flex.
               (substitute-keyword-arguments (package-arguments bison)
                 ((#:tests? _ #f) #f)))
              (inputs (alist-delete "flex" (package-inputs bison))))))
       `(("bison" ,bison-for-tests))))
    ;; m4 is not present in PATH when cross-building
    (native-inputs
     `(("help2man" ,help2man)
       ("m4" ,m4)))
    (propagated-inputs `(("m4" ,m4)))
    (home-page "")
    (synopsis "Fast lexical analyser generator")
    (description
     "Flex is a tool for generating scanners.  A scanner, sometimes
called a tokenizer, is a program which recognizes lexical patterns in
text.  The flex program reads user-specified input files, or its standard
input if no file names are given, for a description of a scanner to
generate.  The description is in the form of pairs of regular expressions
and C code, called rules.  Flex generates a C source file named,
\"lex.yy.c\", which defines the function yylex().  The file \"lex.yy.c\"
can be compiled and linked to produce an executable.  When the executable
is run, it analyzes its input for occurrences of text matching the
regular expressions for each rule.  Whenever it finds a match, it
executes the corresponding C code.")
    (license (non-copyleft "file"
                           "See COPYING in the distribution."))))

 GNU Guix --- Functional package management for GNU

 This file is part of GNU Guix.

 you can redistribute it and/or modify it
 either version 3 of the License , or ( at
 your option) any later version.

 GNU Guix is distributed in the hope that it will be useful, but
 WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 Disable tests, since they require flex.
 m4 is not present in PATH when cross-building
  Copyright © 2012 , 2013 , 2014 , 2019   <  >
  Copyright © 2016   <  >
  under the terms of the GNU General Public License as published by
  You should have received a copy of the GNU General Public License
  along with GNU  .   If not , see < / > .

(define-module (gnu packages flex)
  #:use-module (guix licenses)
  #:use-module (guix packages)
  #:use-module (guix download)
  #:use-module (guix build-system gnu)
  #:use-module (guix utils)
  #:use-module (gnu packages)
  #:use-module (gnu packages m4)
  #:use-module (gnu packages man)
  #:use-module (gnu packages bison)
  #:use-module (srfi srfi-1))

(define-public flex
  (package
    (name "flex")
    (version "2.6.4")
    (source (origin
              (method url-fetch)
              (uri (string-append
                    ""
                    "/releases/download/v" version "/"
                    "flex-" version ".tar.gz"))
              (sha256
               (base32
                "15g9bv236nzi665p9ggqjlfn4dwck5835vf0bbw2cz7h5c1swyp8"))))
    (build-system gnu-build-system)
    (inputs
     (let ((bison-for-tests
            (package
              (inherit bison)
              (arguments
               (substitute-keyword-arguments (package-arguments bison)
                 ((#:tests? _ #f) #f)))
              (inputs (alist-delete "flex" (package-inputs bison))))))
       `(("bison" ,bison-for-tests))))
    (native-inputs
     `(("help2man" ,help2man)
       ("m4" ,m4)))
    (propagated-inputs `(("m4" ,m4)))
    (home-page "")
    (synopsis "Fast lexical analyser generator")
    (description
     "Flex is a tool for generating scanners.  A scanner, sometimes
called a tokenizer, is a program which recognizes lexical patterns in
text.  The flex program reads user-specified input files, or its standard
input if no file names are given, for a description of a scanner to
generate.  The description is in the form of pairs of regular expressions
and C code, called rules.  Flex generates a C source file named,
\"lex.yy.c\", which defines the function yylex().  The file \"lex.yy.c\"
can be compiled and linked to produce an executable.  When the executable
is run, it analyzes its input for occurrences of text matching the
regular expressions for each rule.  Whenever it finds a match, it
executes the corresponding C code.")
    (license (non-copyleft "file"
                           "See COPYING in the distribution."))))
