syntax: Rename '_' to 'G_' to avoid issues on Guile 2.2.

Failing to do that, literal '_' would not match in contexts such as
'match' patterns on Guile 2.2.

* src/guile/skribilo/utils/syntax.scm (_): Rename to...
(G_): ... this.
* po/Makevars (XGETTEXT_OPTIONS): Adjust accordingly.
* src/guile/skribilo.scm,
src/guile/skribilo/ast.scm,
src/guile/skribilo/biblio.scm,
src/guile/skribilo/biblio/author.scm,
src/guile/skribilo/condition.scm,
src/guile/skribilo/engine.scm,
src/guile/skribilo/engine/info.scm,
src/guile/skribilo/engine/lout.scm,
src/guile/skribilo/index.scm,
src/guile/skribilo/package/base.scm,
src/guile/skribilo/package/lncs.scm,
src/guile/skribilo/reader/rss-2.scm,
src/guile/skribilo/source.scm,
src/guile/skribilo/sui.scm,
src/guile/skribilo/biblio/template.scm,
src/guile/skribilo/verify.scm: Use 'G_' instead of '_'.

17 files changed, 106 insertions, 106 deletions

diff --git a/src/guile/skribilo.scm b/src/guile/skribilo.scm
index 1014d8d..4d9b2c6 100644
--- a/src/guile/skribilo.scm
+++ b/src/guile/skribilo.scm
@@ -1,7 +1,7 @@
 ;;; skribilo.scm  --  The Skribilo document processor.
 ;;;
 ;;; Copyright 2005, 2006, 2007, 2008, 2009, 2011, 2012, 2013,
-;;;   2015, 2016  Ludovic Courtès <ludo@gnu.org>
+;;;   2015, 2016, 2018  Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright 2003, 2004  Erick Gallesio - I3S-CNRS/ESSI <eg@unice.fr>
 ;;;
 ;;;
@@ -62,61 +62,61 @@
 ;;;
 
 (define (skribilo-show-help)
-  (display (_ "Usage: skribilo [OPTIONS] [INPUT]"))
-  (display (_ "
+  (display (G_ "Usage: skribilo [OPTIONS] [INPUT]"))
+  (display (G_ "
 Process Skribilo document from file INPUT (or standard input) using the
 specified reader syntax or the 'skribe' syntax, and produce its output using
 the specified engine or the 'html' engine.
 "))
   (newline)
-  (display (_ "\
+  (display (G_ "\
   -R, --reader=READER    use READER to parse the input file;
                          e.g., 'skribe' (default) or 'outline'\n"))
-  (display (_ "\
+  (display (G_ "\
   -t, --target=ENGINE    use ENGINE as the output engine; e.g., 'html'\n"))
-  (display (_ "\
+  (display (G_ "\
   -c, --custom=C=VAL     use VAL as the value of ENGINE's custom C\n"))
-  (display (_ "\
+  (display (G_ "\
   -o, --output=FILE      write output to FILE\n"))
-  (display (_ "\
+  (display (G_ "\
       --compat=COMPAT    use COMPAT as the compatibility layer; e.g., 'skribe'\n"))
   (newline)
-  (display (_ "\
+  (display (G_ "\
   -I, --doc-path=DIR     prepend DIR to the document include path\n"))
-  (display (_ "\
+  (display (G_ "\
   -B, --bib-path=DIR     prepend DIR to the bibliography include path\n"))
-  (display (_ "\
+  (display (G_ "\
   -S, --source-path=DIR  prepend DIR to the source include path\n"))
-  (display (_ "\
+  (display (G_ "\
   -P, --image-path=DIR   prepend DIR to the image include path\n"))
-  (display (_ "\
+  (display (G_ "\
   -U, --sui-path=DIR     prepend DIR to the Skribe URL Index (SUI) search path\n"))
   (newline)
-  (display (_ "\
+  (display (G_ "\
   -b, --base=BASE        strip BASE from all hyperlinks ('html' engine)\n"))
-  (display (_ "\
+  (display (G_ "\
   -e, --eval=EXPR        prepend EXPR to the list of expressions to be
                          evaluted before the input file is processed\n"))
-  (display (_ "\
+  (display (G_ "\
   -p, --preload=FILE     preload FILE before processing the input file\n"))
   (newline)
-  (display (_ "\
+  (display (G_ "\
   -v, --verbose[=LEVEL]  be verbose, unless LEVEL is 0\n"))
-  (display (_ "\
+  (display (G_ "\
   -w, --warning[=LEVEL]  issue warnings, unless LEVEL is 0\n"))
-  (display (_ "\
+  (display (G_ "\
   -g, --debug[=ARG]      issue debugging output, unless ARG is 0; if ARG is
                          not a number, it is interpreted as a symbol to be
                          watched\n"))
-  (display (_ "\
+  (display (G_ "\
       --no-color         disable colored debugging output\n"))
   (newline)
-  (display (_ "\
+  (display (G_ "\
   -h, --help             display this help text and exit\n"))
-  (display (_ "\
+  (display (G_ "\
   -V, --version          display version information and exit\n"))
   (newline)
-  (format #t (_ "\
+  (format #t (G_ "\
 Report bugs to <~a>.~%")
           (skribilo-bug-report-address)))
 
@@ -196,7 +196,7 @@ Report bugs to <~a>.~%")
                 (lambda (opt name arg result)
                   (let ((=-pos (string-index arg #\=)))
                     (if (not =-pos)
-                        (leave (_ "~a: missing value for custom") arg)
+                        (leave (G_ "~a: missing value for custom") arg)
                         (let ((custom (string-take arg =-pos))
                               (value  (string-drop arg (+ =-pos 1))))
                           (catch 'read-error
@@ -213,7 +213,7 @@ Report bugs to <~a>.~%")
                                  (alist-cons custom value customs)
                                  result)))
                             (lambda (key . args)
-                              (leave (_ "~a: invalid custom value")
+                              (leave (G_ "~a: invalid custom value")
                                      value))))))))
         (option '(#\o "output") #t #f
                 (lambda (opt name arg result)
@@ -318,7 +318,7 @@ options."
       (setlocale LC_ALL ""))
     (lambda args
       (format (current-error-port)
-              (_ "warning: failed to install locale: ~a~%")
+              (G_ "warning: failed to install locale: ~a~%")
               (strerror (system-error-errno args)))))
 
   ;; Tell gettext where to look for message catalogs.
diff --git a/src/guile/skribilo/ast.scm b/src/guile/skribilo/ast.scm
index e7a488a..524e654 100644
--- a/src/guile/skribilo/ast.scm
+++ b/src/guile/skribilo/ast.scm
@@ -2,7 +2,7 @@
 ;;;
 ;;; Copyright 2003, 2004, 2009  Erick Gallesio - I3S-CNRS/ESSI <eg@unice.fr>
 ;;; Copyright 2003, 2004  Manuel Serrano
-;;; Copyright 2005, 2006, 2007, 2012, 2013, 2015  Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2005, 2006, 2007, 2012, 2013, 2015, 2018  Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;;
 ;;; This file is part of Skribilo.
@@ -136,21 +136,21 @@
   (cond ((ast-orphan-error? c)
 	 (let ((node (ast-orphan-error:ast c)))
            (show-location node)
-	   (format (current-error-port) (_ "orphan node: ~a~%")
+	   (format (current-error-port) (G_ "orphan node: ~a~%")
 		   node)))
 
 	((ast-cycle-error? c)
 	 (let ((object (ast-cycle-error:object c)))
            (show-location object)
 	   (format (current-error-port)
-		   (_ "cycle found in AST: ~a~%") object)))
+		   (G_ "cycle found in AST: ~a~%") object)))
 
 	((markup-unknown-option-error? c)
 	 (let ((markup (markup-unknown-option-error:markup c))
 	       (option (markup-unknown-option-error:option c)))
            (show-location markup)
 	   (format (current-error-port)
-		   (_ "~a: unknown markup option for '~a'~%")
+		   (G_ "~a: unknown markup option for '~a'~%")
 		   option markup)))
 
 	((markup-already-bound-error? c)
@@ -158,7 +158,7 @@
 	       (ident  (markup-already-bound-error:ident  c)))
            (show-location markup)
 	   (format (current-error-port)
-		   (_ "'~a' (~a): markup identifier already bound~%")
+		   (G_ "'~a' (~a): markup identifier already bound~%")
 		   ident
 		   (if (markup? markup)
 		       (markup-markup markup)
@@ -166,7 +166,7 @@
 
 	(else
 	 (format (current-error-port)
-                 (_ "undefined AST error: ~a~%")
+                 (G_ "undefined AST error: ~a~%")
 		 c))))
 
 (register-error-condition-handler! ast-error? handle-ast-error)
diff --git a/src/guile/skribilo/biblio.scm b/src/guile/skribilo/biblio.scm
index b168d8a..b240f81 100644
--- a/src/guile/skribilo/biblio.scm
+++ b/src/guile/skribilo/biblio.scm
@@ -1,7 +1,7 @@
 ;;; biblio.scm  --  Bibliography functions.
 ;;; -*- coding: iso-8859-1 -*-
 ;;;
-;;; Copyright 2005, 2006, 2007, 2009, 2013  Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2005, 2006, 2007, 2009, 2013, 2018  Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright 2001, 2002, 2003, 2004  Manuel Serrano
 ;;; Copyright 2003, 2004  Erick Gallesio - I3S-CNRS/ESSI <eg@essi.fr>
 ;;;
@@ -108,23 +108,23 @@
                 (line  (source-property entry 'line)))
            (if (and file col line)
                (format (current-error-port)
-                       (_ "~a:~a:~a: invalid bibliography entry: ~a~%")
+                       (G_ "~a:~a:~a: invalid bibliography entry: ~a~%")
                        file line col entry)
                (format (current-error-port)
-                       (_ "invalid bibliography entry: ~a~%")
+                       (G_ "invalid bibliography entry: ~a~%")
                        entry))))
 	((biblio-template-error? c)
 	 (format (current-error-port)
-                 (_ "invalid bibliography entry template: '~a', in '~a'~%")
+                 (G_ "invalid bibliography entry template: '~a', in '~a'~%")
                  (biblio-template-error:expression c)
                  (biblio-template-error:template c)))
         ((biblio-parse-error? c)
          (format (current-error-port)
-                 (_ "invalid bibliography entry s-exp: '~a'~%")
+                 (G_ "invalid bibliography entry s-exp: '~a'~%")
                  (biblio-parse-error:sexp c)))
 	(else
 	 (format (current-error-port)
-                 (_ "undefined bibliography error: ~a~%")
+                 (G_ "undefined bibliography error: ~a~%")
 		 c))))
 
 (register-error-condition-handler! biblio-error?
diff --git a/src/guile/skribilo/biblio/author.scm b/src/guile/skribilo/biblio/author.scm
index 4889d45..6a93348 100644
--- a/src/guile/skribilo/biblio/author.scm
+++ b/src/guile/skribilo/biblio/author.scm
@@ -1,7 +1,7 @@
 ;;; author.scm  --  Handling author names.
 ;;; -*- coding: iso-8859-1 -*-
 ;;;
-;;; Copyright 2006, 2007, 2008, 2009, 2015 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2006, 2007, 2008, 2009, 2015, 2018 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;;
 ;;; This file is part of Skribilo.
@@ -179,7 +179,7 @@
 
    (let ((check-author (lambda (e)
 			  (if (not (markup-option e 'author))
-                              (let ((msg (_ "no author for this bib entry")))
+                              (let ((msg (G_ "no author for this bib entry")))
                                 (raise (condition
                                         (&message
                                          (message (string-append
diff --git a/src/guile/skribilo/biblio/template.scm b/src/guile/skribilo/biblio/template.scm
index fc23b82..b2d2924 100644
--- a/src/guile/skribilo/biblio/template.scm
+++ b/src/guile/skribilo/biblio/template.scm
@@ -1,7 +1,7 @@
 ;;; template.scm  --  Template system for bibliography entries.
 ;;;
 ;;; Copyright 2003, 2004  Manuel Serrano
-;;; Copyright 2006, 2007, 2015 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2006, 2007, 2015, 2018 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;;
 ;;; This file is part of Skribilo.
@@ -150,20 +150,20 @@
      `(author ". " (or title url documenturl) ". "
               ;; TRANSLATORS: The next few msgids are fragments of
               ;; bibliography items.
-              ,(_ "Technical Report") " " number
+              ,(G_ "Technical Report") " " number
               (", " institution)
               (", " address)
               (", " month) " " year
               (", pp. " pages) "."))
     ((article)
      `(author ". " (or title url documenturl) ". "
-              ,(_ "In ") journal ", " volume
+              ,(G_ "In ") journal ", " volume
               ("(" number ") ")", "
               (address ", ") month " " year ", "
               ("pp. " pages) "."))
     ((inproceedings)
      `(author ". " (or title url documenturl) ". "
-              ,(_ "In ") booktitle ", "
+              ,(G_ "In ") booktitle ", "
               (series ", ")
               ("(" number ")")
               ("pp. " pages ", ")
@@ -179,14 +179,14 @@
               (", pp. " pages) "."))
     ((inbook)
      `(author ". " (or title url documenturl) ". "
-              ,(_ "In ") booktitle ", " publisher
-              (", " editor " (" ,(_ "editor") ")")
-              (", " ,(_ "Chapter ") chapter)
+              ,(G_ "In ") booktitle ", " publisher
+              (", " editor " (" ,(G_ "editor") ")")
+              (", " ,(G_ "Chapter ") chapter)
               (", pp. " pages) ", "
               (month " ") year "."))
     ((phdthesis)
      `(author ". " (or title url documenturl)
-              ", " ,(_ "PhD Thesis")
+              ", " ,(G_ "PhD Thesis")
               (", " (or school institution))
               (", " address)
               (", " month)
@@ -210,7 +210,7 @@
   (case kind
     ((techreport)
      `(author " -- " (or title url documenturl) " -- "
-              ,(_ "Technical Report") " " number ", " institution ", "
+              ,(G_ "Technical Report") " " number ", " institution ", "
               address ", " month ", " year ", "
               ("pp. " pages) "."))
     ((article)
diff --git a/src/guile/skribilo/condition.scm b/src/guile/skribilo/condition.scm
index 5c3f684..99e8b4b 100644
--- a/src/guile/skribilo/condition.scm
+++ b/src/guile/skribilo/condition.scm
@@ -1,7 +1,7 @@
 ;;; condition.scm  --  Skribilo SRFI-35 error condition hierarchy.
 ;;; -*- coding: iso-8859-1 -*-
 ;;;
-;;; Copyright 2006, 2007, 2008, 2015 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2006, 2007, 2008, 2015, 2018 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;;
 ;;; This file is part of Skribilo.
@@ -26,7 +26,7 @@
   :use-module (srfi srfi-39)
   :use-module (ice-9 optargs)
   :autoload   (skribilo parameters)   (*destination-file*)
-  :autoload   (skribilo utils syntax) (_ N_)
+  :autoload   (skribilo utils syntax) (G_ N_)
   :export     (&skribilo-error skribilo-error?
 
                invalid-argument-error
@@ -139,8 +139,8 @@
           (format (current-error-port) "~%Call stack:~%")
           (display-backtrace stack (current-error-port)))
         (begin
-          (format (current-error-port) (_ "Call stack trace not available.~%"))
-          (format (current-error-port) (_ "Use 'GUILE=\"guile --debug\" skribilo ...' for a detailed stack trace.~%"))))))
+          (format (current-error-port) (G_ "Call stack trace not available.~%"))
+          (format (current-error-port) (G_ "Use 'GUILE=\"guile --debug\" skribilo ...' for a detailed stack trace.~%"))))))
 
 (define (abort exit-val)
   ;; Abort the `skribilo' command-line program, returning EXIT-VAL.
@@ -160,45 +160,45 @@
              (let ((name (invalid-argument-error:name c)))
                (if name
                    (format (current-error-port)
-                           (_ "in '~a': invalid argument '~a': ~S~%")
+                           (G_ "in '~a': invalid argument '~a': ~S~%")
                            (invalid-argument-error:proc-name c)
                            name
                            (invalid-argument-error:argument c))
                    (format (current-error-port)
-                           (_ "in '~a': invalid argument: ~S~%")
+                           (G_ "in '~a': invalid argument: ~S~%")
                            (invalid-argument-error:proc-name c)
                            (invalid-argument-error:argument c))))
 	     (abort exit-val))
 
 	    ((too-few-arguments-error? c)
 	     (format (current-error-port)
-                     (_ "in '~a': too few arguments: ~S~%")
+                     (G_ "in '~a': too few arguments: ~S~%")
 		     (too-few-arguments-error:proc-name c)
 		     (too-few-arguments-error:arguments c))
              (abort exit-val))
 
 	    ((file-search-error? c)
 	     (format (current-error-port)
-                     (_ "~a: not found in path '~S'~%")
+                     (G_ "~a: not found in path '~S'~%")
 		     (file-error:file-name c)
 		     (file-search-error:path c))
 	     (abort exit-val))
 
 	    ((file-open-error? c)
 	     (format (current-error-port)
-                     (_ "~a: cannot open file~%")
+                     (G_ "~a: cannot open file~%")
 		     (file-error:file-name c))
 	     (abort exit-val))
 
 	    ((file-write-error? c)
 	     (format (current-error-port)
-                     (_ "~a: cannot write to file~%")
+                     (G_ "~a: cannot write to file~%")
 		     (file-error:file-name c))
 	     (abort exit-val))
 
 	    ((file-error? c)
 	     (format (current-error-port)
-                     (_ "file error: ~a~%")
+                     (G_ "file error: ~a~%")
 		     (file-error:file-name c))
 	     (abort exit-val))
 
@@ -207,7 +207,7 @@
 	       (if (procedure? handler)
 		   (handler c)
 		   (format (current-error-port)
-			   (_ "undefined skribilo error: ~S~%")
+			   (G_ "undefined skribilo error: ~S~%")
 			   c)))
 	     (abort exit-val))
 
@@ -217,7 +217,7 @@
 
             (else
              (format (current-error-port)
-                     (_ "unexpected error condition: ~A~%") c)
+                     (G_ "unexpected error condition: ~A~%") c)
              (abort exit-val))))
 
    thunk))
diff --git a/src/guile/skribilo/engine.scm b/src/guile/skribilo/engine.scm
index 25dfa86..fb1bcb2 100644
--- a/src/guile/skribilo/engine.scm
+++ b/src/guile/skribilo/engine.scm
@@ -1,7 +1,7 @@
 ;;; engine.scm	-- Skribilo engines.
 ;;; -*- coding: iso-8859-1 -*-
 ;;;
-;;; Copyright 2005, 2007, 2008, 2009, 2010  Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2005, 2007, 2008, 2009, 2010, 2018  Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright 2003, 2004  Erick Gallesio - I3S-CNRS/ESSI <eg@essi.fr>
 ;;;
 ;;;
@@ -71,12 +71,12 @@
   ;; Issue a user-friendly error message for error condition C.
   (cond ((unknown-engine-error? c)
          (format (current-error-port)
-                 (_ "unknown engine `~a'~%")
+                 (G_ "unknown engine `~a'~%")
                  (unknown-engine-error:engine-name c)))
 
 	(else
 	 (format (current-error-port)
-                 (_ "undefined engine error: ~A~%")
+                 (G_ "undefined engine error: ~A~%")
 		 c))))
 
 (register-error-condition-handler! engine-error? handle-engine-error)
diff --git a/src/guile/skribilo/engine/info.scm b/src/guile/skribilo/engine/info.scm
index ce448d9..13ba77c 100644
--- a/src/guile/skribilo/engine/info.scm
+++ b/src/guile/skribilo/engine/info.scm
@@ -1,7 +1,7 @@
 ;;; info.scm  --  GNU Info engine.
 ;;; -*- coding: iso-8859-1 -*-
 ;;;
-;;; Copyright 2008, 2009, 2012, 2015  Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2008, 2009, 2012, 2015, 2018  Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright 2001, 2002  Manuel Serrano
 ;;;
 ;;;
@@ -174,10 +174,10 @@
                   (begin
                     (skribe-warning/ast 1 section
                                         (format #f
-                                                (_ "Info node title '~A' already used")
+                                                (G_ "Info node title '~A' already used")
                                                 title))
                     (skribe-warning/ast 1 (cdr same-named)
-                                        (_ "previous occurrence was here"))
+                                        (G_ "previous occurrence was here"))
                     section+title)
                   (alist-cons title section section+title))))
           '()
@@ -806,7 +806,7 @@
               (string? (markup-option n :file)))
   :action (lambda (n e)
             (if (markup-option n :url)
-                (skribe-warning/ast 1 n (_ "image URLs are not supported"))
+                (skribe-warning/ast 1 n (G_ "image URLs are not supported"))
                 (let ((f (let ((f (markup-option n :file)))
                            (convert-image f '("png" "gif" "jpg"))))
                       (h (markup-option n :height))
diff --git a/src/guile/skribilo/engine/lout.scm b/src/guile/skribilo/engine/lout.scm
index a059af1..a5afcae 100644
--- a/src/guile/skribilo/engine/lout.scm
+++ b/src/guile/skribilo/engine/lout.scm
@@ -2,7 +2,7 @@
 ;;; -*- coding: iso-8859-1 -*-
 ;;;
 ;;; Copyright 2004, 2005, 2006, 2007, 2008, 2009, 2010,
-;;;  2012, 2015  Ludovic Courtès <ludo@gnu.org>
+;;;  2012, 2015, 2018  Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;;
 ;;; This file is part of Skribilo.
@@ -2422,7 +2422,7 @@
 						     '("eps"))))))
 		(cond (url ;; maybe we should run `wget' then?  :-)
                        (skribe-warning/ast 1 n
-                                           (_ "image URLs are not supported")))
+                                           (G_ "image URLs are not supported")))
 
                       ((string? img)
                        (if width
diff --git a/src/guile/skribilo/index.scm b/src/guile/skribilo/index.scm
index 50ef4f0..d9616b4 100644
--- a/src/guile/skribilo/index.scm
+++ b/src/guile/skribilo/index.scm
@@ -1,6 +1,6 @@
 ;;; index.scm -- Document indices.        -*- coding: iso-8859-1 -*-
 ;;;
-;;; Copyright 2005, 2006, 2008, 2009, 2015  Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2005, 2006, 2008, 2009, 2015, 2018  Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright 2003, 2004  Manuel Serrano
 ;;;
 ;;;
@@ -94,7 +94,7 @@
                                     (location-column loc))
                             ""))
                    (msg (format
-                         #f (_ "the-index: char offset '~A' out of bounds~%")
+                         #f (G_ "the-index: char offset '~A' out of bounds~%")
                          char-offset)))
                (raise (condition (&message
                                   (condition-message (string-append loc msg))))))
diff --git a/src/guile/skribilo/package/base.scm b/src/guile/skribilo/package/base.scm
index f5a4829..fa89c81 100644
--- a/src/guile/skribilo/package/base.scm
+++ b/src/guile/skribilo/package/base.scm
@@ -1,7 +1,7 @@
 ;;; base.scm -- The base markup package of Skribe/Skribilo.
 ;;; -*- coding: iso-8859-1 -*-
 ;;;
-;;; Copyright 2005, 2006, 2007, 2008, 2009, 2013, 2015, 2016 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2005, 2006, 2007, 2008, 2009, 2013, 2015, 2016, 2018 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright 2003, 2004  Manuel Serrano
 ;;;
 ;;;
@@ -539,21 +539,21 @@
                         ;; 'definition' denote parameter names; they must not
                         ;; be translated.  Likewise for the 3 subsequent
                         ;; strings.
-			(_ "file, start/stop, and definition\
+			(G_ "file, start/stop, and definition\
  cannot be combined with body")
 			body))
 	 ((and start stop definition)
 	  (skribe-error 'source
-			(_ "start/stop are exclusive with a definition")
+			(G_ "start/stop are exclusive with a definition")
 			body))
 	 ((and (or start stop definition) (not file))
 	  (skribe-error 'source
-			(_ "start/stop and definition require a\
+			(G_ "start/stop and definition require a\
  file specification")
 			file))
 	 ((and definition (not language))
 	  (skribe-error 'source
-			(_ "definition requires a language specification")
+			(G_ "definition requires a language specification")
 			definition))
 	 ((and file (not (string? file)))
           (invalid-argument-error 'source file 'file))
@@ -563,7 +563,7 @@
           (invalid-argument-error 'source stop 'stop))
 	 ((and (integer? start) (integer? stop) (> start stop))
 	  (skribe-error 'source
-			(_ "start line is greater than stop line")
+			(G_ "start line is greater than stop line")
 			(format #f "~a/~a" start stop)))
 	 ((and language (not (language? language)))
           (invalid-argument-error 'source language 'language))
diff --git a/src/guile/skribilo/package/lncs.scm b/src/guile/skribilo/package/lncs.scm
index 8a3acbe..4678e76 100644
--- a/src/guile/skribilo/package/lncs.scm
+++ b/src/guile/skribilo/package/lncs.scm
@@ -2,7 +2,7 @@
 ;;; -*- coding: iso-8859-1 -*-
 ;;;
 ;;; Copyright 2003, 2004  Manuel Serrano
-;;; Copyright 2007, 2015  Ludovic Courtès <ludovic.courtes@laas.fr>
+;;; Copyright 2007, 2015, 2018  Ludovic Courtès <ludovic.courtes@laas.fr>
 ;;;
 ;;;
 ;;; This file is part of Skribilo.
@@ -214,20 +214,20 @@
      `(author ": " (or title url documenturl) ". "
               ;; TRANSLATORS: The next few msgids are fragments of
               ;; bibliography items.
-              ,(_ "Technical Report") " " number
+              ,(G_ "Technical Report") " " number
               (", " institution)
               (", " address)
               (", " pages)
               (" (" year ")")))
     ((article)
      `(author ": " (or title url documenturl) ". "
-              ,(_ "In: ") journal ", " volume
+              ,(G_ "In: ") journal ", " volume
               ("(" number ")") ", "
               (address ", ")
               ("pp. " pages) (" (" year ")")))
     ((inproceedings)
      '(author ": " (or title url documenturl) ". "
-              ,(_ "In: ") booktitle ", "
+              ,(G_ "In: ") booktitle ", "
               (series)
               ("(" number "), ")
               (publisher ", ")
@@ -243,14 +243,14 @@
        (", pp. " pages)))
     ((inbook)
      `(author ": " (or title url documenturl) ". "
-              ,(_ "In: ") booktitle ", " publisher
-              (", " editor " (" ,(_ "editor") ")")
-              (", " ,(_ "Chapter ") chapter)
+              ,(G_ "In: ") booktitle ", " publisher
+              (", " editor " (" ,(G_ "editor") ")")
+              (", " ,(G_ "Chapter ") chapter)
               (", pp. " pages)
               (" (" year ")")))
     ((phdthesis)
      `(author ": " (or title url documenturl)
-              ", " ,(_ "PhD Thesis")
+              ", " ,(G_ "PhD Thesis")
               (", " (or school institution))
               (", " address)
               (", " month)
diff --git a/src/guile/skribilo/reader/rss-2.scm b/src/guile/skribilo/reader/rss-2.scm
index 6bdd753..84f452a 100755
--- a/src/guile/skribilo/reader/rss-2.scm
+++ b/src/guile/skribilo/reader/rss-2.scm
@@ -1,6 +1,6 @@
 ;;; rss-2.scm  --  A reader for RSS 2.0 files.
 ;;;
-;;; Copyright 2008, 2011  Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2008, 2011, 2018  Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;;
 ;;; This file is part of Skribilo.
@@ -67,7 +67,7 @@
     (_
      (raise (condition
              (&message
-              (message (_ "input is not a valid RSS 2.0 feed"))))))))
+              (message (G_ "input is not a valid RSS 2.0 feed"))))))))
 
 (define (channel-items channel)
   ;; Return the list of items of CHANNEL, an SXML tree.
@@ -239,14 +239,14 @@
        `(list ,@(loop (html->shtml body))))
 
       (((? symbol? unsupported-tag) rest ...)
-       (warn* (_ "tag '~s' ignored") tag)
+       (warn* (G_ "tag '~s' ignored") tag)
        #f)
 
       ((lst ...)
        (map loop lst))
 
       (_
-       (warn* (_ "skipping tag '~a'~%") tag)
+       (warn* (G_ "skipping tag '~a'~%") tag)
        #f))))
 
 (define (english-date->date str)
@@ -297,7 +297,7 @@
     (if (null? channels)
         (raise (condition
                 (&message
-                 (message (_ "no RSS 2.0 channels found in feed")))))
+                 (message (G_ "no RSS 2.0 channels found in feed")))))
         (let ((title   (channel-title (car channels)))
               (single? (null? (cdr channels))))
           ;; When there's only one channel, promote items as chapters.
diff --git a/src/guile/skribilo/source.scm b/src/guile/skribilo/source.scm
index 39a5eeb..b1e1e1d 100644
--- a/src/guile/skribilo/source.scm
+++ b/src/guile/skribilo/source.scm
@@ -1,7 +1,7 @@
 ;;; source.scm	-- Highlighting source files.
 ;;; -*- coding: iso-8859-1 -*-
 ;;;
-;;; Copyright 2005, 2008, 2009, 2010  Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2005, 2008, 2009, 2010, 2018  Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright 2003, 2004  Erick Gallesio - I3S-CNRS/ESSI <eg@essi.fr>
 ;;;
 ;;;
@@ -67,18 +67,18 @@
   ;; Issue a user-friendly error message for error condition C.
   (cond ((no-extractor-error? c)
          (format (current-error-port)
-                 (_ "source language '~a' does not have an extractor~%")
+                 (G_ "source language '~a' does not have an extractor~%")
                  (language-name (no-extractor-error:language c))))
 
         ((definition-not-found-error? c)
          (format (current-error-port)
-                 (_ "source definition of '~a' in language '~a' not found~%")
+                 (G_ "source definition of '~a' in language '~a' not found~%")
                  (definition-not-found-error:definition c)
                  (language-name (definition-not-found-error:language c))))
 
 	(else
 	 (format (current-error-port)
-                 (_ "undefined source error: ~A~%")
+                 (G_ "undefined source error: ~A~%")
 		 c))))
 
 (register-error-condition-handler! source-error? handle-source-error)
diff --git a/src/guile/skribilo/sui.scm b/src/guile/skribilo/sui.scm
index d4bf071..34e146a 100644
--- a/src/guile/skribilo/sui.scm
+++ b/src/guile/skribilo/sui.scm
@@ -1,7 +1,7 @@
 ;;; sui.scm -- Skribe URL Indices
 ;;;
 ;;; Copyright (C) 2005, 2006, 2007, 2008, 2009, 2012,
-;;;    2015  Ludovic Courtès <ludo@gnu.org>
+;;;    2015, 2018  Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright (C) 2003, 2004  Manuel Serrano
 ;;;
 ;;;
@@ -79,12 +79,12 @@
 	 (let ((sexp (invalid-sui-error:sexp c)))
            (show-location sexp)
 	   (format (current-error-port)
-                   (_ "invalid SUI form: ~A~%")
+                   (G_ "invalid SUI form: ~A~%")
                    sexp)))
 
 	(else
 	 (format (current-error-port)
-                 (_ "undefined SUI error: ~A~%")
+                 (G_ "undefined SUI error: ~A~%")
 		 c))))
 
 (register-error-condition-handler! sui-error? handle-sui-error)
diff --git a/src/guile/skribilo/utils/syntax.scm b/src/guile/skribilo/utils/syntax.scm
index 9477095..b6c93b4 100644
--- a/src/guile/skribilo/utils/syntax.scm
+++ b/src/guile/skribilo/utils/syntax.scm
@@ -1,7 +1,7 @@
 ;;; syntax.scm  --  Syntactic candy for Skribilo modules. -*- coding: utf-8 -*-
 ;;;
 ;;; Copyright 2005, 2006, 2007, 2008, 2009, 2010, 2011,
-;;;   2012, 2016 Ludovic Courtès <ludo@gnu.org>
+;;;   2012, 2016, 2018 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;;
 ;;; This file is part of Skribilo.
@@ -28,7 +28,7 @@
            set-correct-file-encoding!
            default-to-utf-8
            %skribilo-text-domain
-           _ N_
+           G_ N_
            unwind-protect))
 
 ;;; Author:  Ludovic Courtès
@@ -54,7 +54,7 @@
 		     (if (string? file)
 			 (format #f "~a:~a:~a: " file line column)
 			 "")
-		     (_ "unexpected character in Skribilo module"))
+		     (G_ "unexpected character in Skribilo module"))
 		    chr)))
 
          (cond-expand
@@ -132,7 +132,7 @@
 
 (textdomain %skribilo-text-domain)
 
-(define (_ msg)
+(define (G_ msg)
   (gettext msg %skribilo-text-domain))
 
 (define (N_ msg msgplural n)
diff --git a/src/guile/skribilo/verify.scm b/src/guile/skribilo/verify.scm
index cf07e55..0f9bf5d 100644
--- a/src/guile/skribilo/verify.scm
+++ b/src/guile/skribilo/verify.scm
@@ -1,7 +1,7 @@
 ;;; verify.scm  --  Skribe AST verification.
 ;;; -*- coding: iso-8859-1 -*-
 ;;;
-;;; Copyright 2005, 2007, 2008  Ludovic Courtès <ludo@gnu.org>
+;;; Copyright 2005, 2007, 2008, 2018  Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright 2003, 2004  Erick Gallesio - I3S-CNRS/ESSI <eg@unice.fr>
 ;;;
 ;;;
@@ -72,14 +72,14 @@
                (option (unsupported-markup-option-error:option c)))
            (show-location node)
 	   (format (current-error-port)
-                   (_ "option '~a' of markup '~a' not supported by engine '~a'~%")
+                   (G_ "option '~a' of markup '~a' not supported by engine '~a'~%")
 		   option (and (markup? node)
                                (markup-markup node))
                    (engine-ident engine))))
 
 	(else
 	 (format (current-error-port)
-                 (_ "undefined verify error: ~a~%")
+                 (G_ "undefined verify error: ~a~%")
 		 c))))
 
 (register-error-condition-handler! verify-error? handle-verify-error)