* gnu/packages.scm (fold-available-packages): New procedure.
* guix/scripts/package.scm (process-query): Use it instead of
'fold-packages'.
* tests/packages.scm ("fold-available-packages with/without cache"):
New test.
		
	
			
		
			
				
	
	
		
			521 lines
		
	
	
	
		
			20 KiB
		
	
	
	
		
			Scheme
		
	
	
	
	
	
			
		
		
	
	
			521 lines
		
	
	
	
		
			20 KiB
		
	
	
	
		
			Scheme
		
	
	
	
	
	
| ;;; GNU Guix --- Functional package management for GNU
 | ||
| ;;; Copyright © 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.org>
 | ||
| ;;; Copyright © 2013 Mark H Weaver <mhw@netris.org>
 | ||
| ;;; Copyright © 2014 Eric Bavier <bavier@member.fsf.org>
 | ||
| ;;; Copyright © 2016, 2017 Alex Kost <alezost@gmail.com>
 | ||
| ;;; Copyright © 2016 Mathieu Lirzin <mthl@gnu.org>
 | ||
| ;;;
 | ||
| ;;; This file is part of GNU Guix.
 | ||
| ;;;
 | ||
| ;;; GNU Guix 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.
 | ||
| ;;;
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| ;;; You should have received a copy of the GNU General Public License
 | ||
| ;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
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| 
 | ||
| (define-module (gnu packages)
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|   #:use-module (guix packages)
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|   #:use-module (guix ui)
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|   #:use-module (guix utils)
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|   #:use-module (guix discovery)
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|   #:use-module (guix memoization)
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|   #:use-module ((guix build utils)
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|                 #:select ((package-name->name+version
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|                            . hyphen-separated-name->name+version)
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|                           mkdir-p))
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|   #:autoload   (guix profiles) (packages->manifest)
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|   #:use-module (guix describe)
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|   #:use-module (ice-9 vlist)
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|   #:use-module (ice-9 match)
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|   #:autoload   (ice-9 binary-ports) (put-bytevector)
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|   #:autoload   (system base compile) (compile)
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|   #:use-module (srfi srfi-1)
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|   #:use-module (srfi srfi-11)
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|   #:use-module (srfi srfi-26)
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|   #:use-module (srfi srfi-34)
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|   #:use-module (srfi srfi-35)
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|   #:use-module (srfi srfi-39)
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|   #:export (search-patch
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|             search-patches
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|             search-auxiliary-file
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|             search-bootstrap-binary
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|             %patch-path
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|             %auxiliary-files-path
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|             %bootstrap-binaries-path
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|             %package-module-path
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|             %default-package-module-path
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| 
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|             fold-packages
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|             fold-available-packages
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| 
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|             find-packages-by-name
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|             find-package-locations
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|             find-best-packages-by-name
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| 
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|             specification->package
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|             specification->package+output
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|             specification->location
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|             specifications->manifest
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| 
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|             generate-package-cache))
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| 
 | ||
| ;;; Commentary:
 | ||
| ;;;
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| ;;; General utilities for the software distribution---i.e., the modules under
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| ;;; (gnu packages ...).
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| ;;;
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| ;;; Code:
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| 
 | ||
| ;; By default, we store patches, auxiliary files and bootstrap binaries
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| ;; alongside Guile modules.  This is so that these extra files can be
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| ;; found without requiring a special setup, such as a specific
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| ;; installation directory and an extra environment variable.  One
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| ;; advantage of this setup is that everything just works in an
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| ;; auto-compilation setting.
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| 
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| (define %bootstrap-binaries-path
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|   (make-parameter
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|    (map (cut string-append <> "/gnu/packages/bootstrap")
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|         %load-path)))
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| 
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| (define %auxiliary-files-path
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|   (make-parameter
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|    (map (cut string-append <> "/gnu/packages/aux-files")
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|         %load-path)))
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| 
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| (define (search-auxiliary-file file-name)
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|   "Search the auxiliary FILE-NAME.  Return #f if not found."
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|   (search-path (%auxiliary-files-path) file-name))
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| 
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| (define (search-patch file-name)
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|   "Search the patch FILE-NAME.  Raise an error if not found."
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|   (or (search-path (%patch-path) file-name)
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|       (raise (condition
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|               (&message (message (format #f (G_ "~a: patch not found")
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|                                          file-name)))))))
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| 
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| (define-syntax-rule (search-patches file-name ...)
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|   "Return the list of absolute file names corresponding to each
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| FILE-NAME found in %PATCH-PATH."
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|   (list (search-patch file-name) ...))
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| 
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| (define (search-bootstrap-binary file-name system)
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|   "Search the bootstrap binary FILE-NAME for SYSTEM.  Raise an error if not
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| found."
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|   (or (search-path (%bootstrap-binaries-path)
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|                    (string-append system "/" file-name))
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|       (raise (condition
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|               (&message
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|                (message
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|                 (format #f (G_ "could not find bootstrap binary '~a' \
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| for system '~a'")
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|                         file-name system)))))))
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| 
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| (define %distro-root-directory
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|   ;; Absolute file name of the module hierarchy.  Since (gnu packages …) might
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|   ;; live in a directory different from (guix), try to get the best match.
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|   (letrec-syntax ((dirname* (syntax-rules ()
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|                               ((_ file)
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|                                (dirname file))
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|                               ((_ file head tail ...)
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|                                (dirname (dirname* file tail ...)))))
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|                   (try      (syntax-rules ()
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|                               ((_ (file things ...) rest ...)
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|                                (match (search-path %load-path file)
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|                                  (#f
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|                                   (try rest ...))
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|                                  (absolute
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|                                   (dirname* absolute things ...))))
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|                               ((_)
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|                                #f))))
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|     (try ("gnu/packages/base.scm" gnu/ packages/)
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|          ("gnu/packages.scm"      gnu/)
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|          ("guix.scm"))))
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| 
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| (define %default-package-module-path
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|   ;; Default search path for package modules.
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|   `((,%distro-root-directory . "gnu/packages")))
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| 
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| (define (cache-is-authoritative?)
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|   "Return true if the pre-computed package cache is authoritative.  It is not
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| authoritative when entries have been added via GUIX_PACKAGE_PATH or '-L'
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| flags."
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|   (equal? (%package-module-path)
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|           (append %default-package-module-path
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|                   (package-path-entries))))
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| 
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| (define %package-module-path
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|   ;; Search path for package modules.  Each item must be either a directory
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|   ;; name or a pair whose car is a directory and whose cdr is a sub-directory
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|   ;; to narrow the search.
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|   (let* ((not-colon   (char-set-complement (char-set #\:)))
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|          (environment (string-tokenize (or (getenv "GUIX_PACKAGE_PATH") "")
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|                                        not-colon))
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|          (channels    (package-path-entries)))
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|     ;; Automatically add channels and items from $GUIX_PACKAGE_PATH to Guile's
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|     ;; search path.  For historical reasons, $GUIX_PACKAGE_PATH goes to the
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|     ;; front; channels go to the back so that they don't override Guix' own
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|     ;; modules.
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|     (set! %load-path
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|       (append environment %load-path channels))
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|     (set! %load-compiled-path
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|       (append environment %load-compiled-path channels))
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| 
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|     (make-parameter
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|      (append environment
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|              %default-package-module-path
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|              channels))))
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| 
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| (define %patch-path
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|   ;; Define it after '%package-module-path' so that '%load-path' contains user
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|   ;; directories, allowing patches in $GUIX_PACKAGE_PATH to be found.
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|   (make-parameter
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|    (map (lambda (directory)
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|           (if (string=? directory %distro-root-directory)
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|               (string-append directory "/gnu/packages/patches")
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|               directory))
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|         %load-path)))
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| 
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| (define (fold-available-packages proc init)
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|   "Fold PROC over the list of available packages.  For each available package,
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| PROC is called along these lines:
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| 
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|   (PROC NAME VERSION RESULT
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|         #:outputs OUTPUTS
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|         #:location LOCATION
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|         …)
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| 
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| PROC can use #:allow-other-keys to ignore the bits it's not interested in.
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| When a package cache is available, this procedure does not actually load any
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| package module."
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|   (define cache
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|     (load-package-cache (current-profile)))
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| 
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|   (if (and cache (cache-is-authoritative?))
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|       (vhash-fold (lambda (name vector result)
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|                     (match vector
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|                       (#(name version module symbol outputs
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|                               supported? deprecated?
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|                               file line column)
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|                        (proc name version result
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|                              #:outputs outputs
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|                              #:location (and file
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|                                              (location file line column))
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|                              #:supported? supported?
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|                              #:deprecated? deprecated?))))
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|                   init
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|                   cache)
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|       (fold-packages (lambda (package result)
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|                        (proc (package-name package)
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|                              (package-version package)
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|                              result
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|                              #:outputs (package-outputs package)
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|                              #:location (package-location package)
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|                              #:supported?
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|                              (->bool
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|                               (member (%current-system)
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|                                       (package-supported-systems package)))
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|                              #:deprecated?
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|                              (->bool
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|                               (package-superseded package))))
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|                      init)))
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| 
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| (define* (fold-packages proc init
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|                         #:optional
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|                         (modules (all-modules (%package-module-path)
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|                                               #:warn
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|                                               warn-about-load-error))
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|                         #:key (select? (negate hidden-package?)))
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|   "Call (PROC PACKAGE RESULT) for each available package defined in one of
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| MODULES that matches SELECT?, using INIT as the initial value of RESULT.  It
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| is guaranteed to never traverse the same package twice."
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|   (fold-module-public-variables (lambda (object result)
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|                                   (if (and (package? object) (select? object))
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|                                       (proc object result)
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|                                       result))
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|                                 init
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|                                 modules))
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| 
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| (define %package-cache-file
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|   ;; Location of the package cache.
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|   "/lib/guix/package.cache")
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| 
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| (define load-package-cache
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|   (mlambda (profile)
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|     "Attempt to load the package cache.  On success return a vhash keyed by
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| package names.  Return #f on failure."
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|     (match profile
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|       (#f #f)
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|       (profile
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|        (catch 'system-error
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|          (lambda ()
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|            (define lst
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|              (load-compiled (string-append profile %package-cache-file)))
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|            (fold (lambda (item vhash)
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|                    (match item
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|                      (#(name version module symbol outputs
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|                              supported? deprecated?
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|                              file line column)
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|                       (vhash-cons name item vhash))))
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|                  vlist-null
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|                  lst))
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|          (lambda args
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|            (if (= ENOENT (system-error-errno args))
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|                #f
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|                (apply throw args))))))))
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| 
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| (define find-packages-by-name/direct              ;bypass the cache
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|   (let ((packages (delay
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|                     (fold-packages (lambda (p r)
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|                                      (vhash-cons (package-name p) p r))
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|                                    vlist-null)))
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|         (version>? (lambda (p1 p2)
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|                      (version>? (package-version p1) (package-version p2)))))
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|     (lambda* (name #:optional version)
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|       "Return the list of packages with the given NAME.  If VERSION is not #f,
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| then only return packages whose version is prefixed by VERSION, sorted in
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| decreasing version order."
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|       (let ((matching (sort (vhash-fold* cons '() name (force packages))
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|                             version>?)))
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|         (if version
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|             (filter (lambda (package)
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|                       (version-prefix? version (package-version package)))
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|                     matching)
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|             matching)))))
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| 
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| (define (cache-lookup cache name)
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|   "Lookup package NAME in CACHE.  Return a list sorted in increasing version
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| order."
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|   (define (package-version<? v1 v2)
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|     (version>? (vector-ref v2 1) (vector-ref v1 1)))
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| 
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|   (sort (vhash-fold* cons '() name cache)
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|         package-version<?))
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| 
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| (define* (find-packages-by-name name #:optional version)
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|   "Return the list of packages with the given NAME.  If VERSION is not #f,
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| then only return packages whose version is prefixed by VERSION, sorted in
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| decreasing version order."
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|   (define cache
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|     (load-package-cache (current-profile)))
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| 
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|   (if (and (cache-is-authoritative?) cache)
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|       (match (cache-lookup cache name)
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|         (#f #f)
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|         ((#(_ versions modules symbols _ _ _ _ _ _) ...)
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|          (fold (lambda (version* module symbol result)
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|                  (if (or (not version)
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|                          (version-prefix? version version*))
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|                      (cons (module-ref (resolve-interface module)
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|                                        symbol)
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|                            result)
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|                      result))
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|                '()
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|                versions modules symbols)))
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|       (find-packages-by-name/direct name version)))
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| 
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| (define* (find-package-locations name #:optional version)
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|   "Return a list of version/location pairs corresponding to each package
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| matching NAME and VERSION."
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|   (define cache
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|     (load-package-cache (current-profile)))
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| 
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|   (if (and cache (cache-is-authoritative?))
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|       (match (cache-lookup cache name)
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|         (#f '())
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|         ((#(name versions modules symbols outputs
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|                  supported? deprecated?
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|                  files lines columns) ...)
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|          (fold (lambda (version* file line column result)
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|                  (if (and file
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|                           (or (not version)
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|                               (version-prefix? version version*)))
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|                      (alist-cons version* (location file line column)
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|                                  result)
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|                      result))
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|                '()
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|                versions files lines columns)))
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|       (map (lambda (package)
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|              (cons (package-version package) (package-location package)))
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|            (find-packages-by-name/direct name version))))
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| 
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| (define (find-best-packages-by-name name version)
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|   "If version is #f, return the list of packages named NAME with the highest
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| version numbers; otherwise, return the list of packages named NAME and at
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| VERSION."
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|   (if version
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|       (find-packages-by-name name version)
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|       (match (find-packages-by-name name)
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|         (()
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|          '())
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|         ((matches ...)
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|          ;; Return the subset of MATCHES with the higher version number.
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|          (let ((highest (package-version (first matches))))
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|            (take-while (lambda (p)
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|                          (string=? (package-version p) highest))
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|                        matches))))))
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| 
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| (define (generate-package-cache directory)
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|   "Generate under DIRECTORY a cache of all the available packages.
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| 
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| The primary purpose of the cache is to speed up package lookup by name such
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| that we don't have to traverse and load all the package modules, thereby also
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| reducing the memory footprint."
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|   (define cache-file
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|     (string-append directory %package-cache-file))
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| 
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|   (define (expand-cache module symbol variable result)
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|     (match (false-if-exception (variable-ref variable))
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|       ((? package? package)
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|        (if (hidden-package? package)
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|            result
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|            (cons `#(,(package-name package)
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|                     ,(package-version package)
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|                     ,(module-name module)
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|                     ,symbol
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|                     ,(package-outputs package)
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|                     ,(->bool (member (%current-system)
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|                                      (package-supported-systems package)))
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|                     ,(->bool (package-superseded package))
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|                     ,@(let ((loc (package-location package)))
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|                         (if loc
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|                             `(,(location-file loc)
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|                               ,(location-line loc)
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|                               ,(location-column loc))
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|                             '(#f #f #f))))
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|                  result)))
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|       (_
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|        result)))
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| 
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|   (define exp
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|     (fold-module-public-variables* expand-cache '()
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|                                    (all-modules (%package-module-path)
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|                                                 #:warn
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|                                                 warn-about-load-error)))
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| 
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|   (mkdir-p (dirname cache-file))
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|   (call-with-output-file cache-file
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|     (lambda (port)
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|       ;; Store the cache as a '.go' file.  This makes loading fast and reduces
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|       ;; heap usage since some of the static data is directly mmapped.
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|       (put-bytevector port
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|                       (compile `'(,@exp)
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|                                #:to 'bytecode
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|                                #:opts '(#:to-file? #t)))))
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|   cache-file)
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| 
 | ||
| 
 | ||
| (define %sigint-prompt
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|   ;; The prompt to jump to upon SIGINT.
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|   (make-prompt-tag "interruptible"))
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| 
 | ||
| (define (call-with-sigint-handler thunk handler)
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|   "Call THUNK and return its value.  Upon SIGINT, call HANDLER with the signal
 | ||
| number in the context of the continuation of the call to this function, and
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| return its return value."
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|   (call-with-prompt %sigint-prompt
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|                     (lambda ()
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|                       (sigaction SIGINT
 | ||
|                         (lambda (signum)
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|                           (sigaction SIGINT SIG_DFL)
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|                           (abort-to-prompt %sigint-prompt signum)))
 | ||
|                       (dynamic-wind
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|                         (const #t)
 | ||
|                         thunk
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|                         (cut sigaction SIGINT SIG_DFL)))
 | ||
|                     (lambda (k signum)
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|                       (handler signum))))
 | ||
| 
 | ||
| 
 | ||
| ;;;
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| ;;; Package specification.
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| ;;;
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| 
 | ||
| (define* (%find-package spec name version)
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|   (match (find-best-packages-by-name name version)
 | ||
|     ((pkg . pkg*)
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|      (unless (null? pkg*)
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|        (warning (G_ "ambiguous package specification `~a'~%") spec)
 | ||
|        (warning (G_ "choosing ~a@~a from ~a~%")
 | ||
|                 (package-name pkg) (package-version pkg)
 | ||
|                 (location->string (package-location pkg))))
 | ||
|      (match (package-superseded pkg)
 | ||
|        ((? package? new)
 | ||
|         (info (G_ "package '~a' has been superseded by '~a'~%")
 | ||
|               (package-name pkg) (package-name new))
 | ||
|         new)
 | ||
|        (#f
 | ||
|         pkg)))
 | ||
|     (x
 | ||
|      (if version
 | ||
|          (leave (G_ "~A: package not found for version ~a~%") name version)
 | ||
|          (leave (G_ "~A: unknown package~%") name)))))
 | ||
| 
 | ||
| (define (specification->package spec)
 | ||
|   "Return a package matching SPEC.  SPEC may be a package name, or a package
 | ||
| name followed by an at-sign and a version number.  If the version number is not
 | ||
| present, return the preferred newest version."
 | ||
|   (let-values (((name version) (package-name->name+version spec)))
 | ||
|     (%find-package spec name version)))
 | ||
| 
 | ||
| (define (specification->location spec)
 | ||
|   "Return the location of the highest-numbered package matching SPEC, a
 | ||
| specification such as \"guile@2\" or \"emacs\"."
 | ||
|   (let-values (((name version) (package-name->name+version spec)))
 | ||
|     (match (find-package-locations name version)
 | ||
|       (()
 | ||
|        (if version
 | ||
|            (leave (G_ "~A: package not found for version ~a~%") name version)
 | ||
|            (leave (G_ "~A: unknown package~%") name)))
 | ||
|       (lst
 | ||
|        (let* ((highest   (match lst (((version . _) _ ...) version)))
 | ||
|               (locations (take-while (match-lambda
 | ||
|                                        ((version . location)
 | ||
|                                         (string=? version highest)))
 | ||
|                                      lst)))
 | ||
|          (match locations
 | ||
|            (((version . location) . rest)
 | ||
|             (unless (null? rest)
 | ||
|               (warning (G_ "ambiguous package specification `~a'~%") spec)
 | ||
|               (warning (G_ "choosing ~a@~a from ~a~%")
 | ||
|                        name version
 | ||
|                        (location->string location)))
 | ||
|             location)))))))
 | ||
| 
 | ||
| (define* (specification->package+output spec #:optional (output "out"))
 | ||
|   "Return the package and output specified by SPEC, or #f and #f; SPEC may
 | ||
| optionally contain a version number and an output name, as in these examples:
 | ||
| 
 | ||
|   guile
 | ||
|   guile@2.0.9
 | ||
|   guile:debug
 | ||
|   guile@2.0.9:debug
 | ||
| 
 | ||
| If SPEC does not specify a version number, return the preferred newest
 | ||
| version; if SPEC does not specify an output, return OUTPUT."
 | ||
|   (let-values (((name version sub-drv)
 | ||
|                 (package-specification->name+version+output spec output)))
 | ||
|     (match (%find-package spec name version)
 | ||
|       (#f
 | ||
|        (values #f #f))
 | ||
|       (package
 | ||
|        (if (member sub-drv (package-outputs package))
 | ||
|            (values package sub-drv)
 | ||
|            (leave (G_ "package `~a' lacks output `~a'~%")
 | ||
|                   (package-full-name package)
 | ||
|                   sub-drv))))))
 | ||
| 
 | ||
| (define (specifications->manifest specs)
 | ||
|   "Given SPECS, a list of specifications such as \"emacs@25.2\" or
 | ||
| \"guile:debug\", return a profile manifest."
 | ||
|   ;; This procedure exists mostly so users of 'guix package -m' don't have to
 | ||
|   ;; fiddle with multiple-value returns.
 | ||
|   (packages->manifest
 | ||
|    (map (compose list specification->package+output) specs)))
 |