From 7b42b6e264b475b438ac4bcd31029942d4b04925 Mon Sep 17 00:00:00 2001
From: Martin Mares <mj@ucw.cz>
Date: Tue, 5 Jun 2018 19:37:33 +0200
Subject: [PATCH] Added a simple localization mechanism

---
 ucw-algo.tex | 19 ++++++++++---------
 ucwmac.tex   | 18 ++++++++++++++++++
 2 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/ucw-algo.tex b/ucw-algo.tex
index 961e319..6259fbc 100644
--- a/ucw-algo.tex
+++ b/ucw-algo.tex
@@ -11,10 +11,11 @@
 %	\algout output description
 %	\endalgo
 
-\def\localealgo{Algorithm}
-\def\localeproc{Procedure}
-\def\localeinput{Input}
-\def\localeoutput{Output}
+% Localized strings
+\localedef{en}{alg:alg}{Algorithm}
+\localedef{en}{alg:proc}{Procedure}
+\localedef{en}{alg:in}{Input}
+\localedef{en}{alg:out}{Output}
 
 \def\algoinit{
 \goodbreak
@@ -29,8 +30,8 @@
 \itemcount=0
 }
 \def\typedalgo#1#2{\algoinit {\bo #1\/} \alg{#2}}
-\def\algo#1{\typedalgo{\localealgo}{#1}}
-\def\proc#1{\typedalgo{\localeproc}{#1}}
+\def\algo#1{\typedalgo{\localestr{alg:alg}}{#1}}
+\def\proc#1{\typedalgo{\localestr{alg:proc}}{#1}}
 \def\headlessalgo{\algoinit}
 \def\endalgo{\goodbreak\endlist\endgroup}
 \let\endproc=\endalgo
@@ -48,9 +49,9 @@
 \def\algoitemh{\ifx\next:\let\next=\algohang\else\let\next=\algoitemgo\fi\next}
 \def\algohang:{\advance\hangindent by 2em \hskip 2em\futurelet\next\algoitemh}
 \optdef\algoitemgo{\ifx\addid\undefined\else\addid{item}{\the\itemcount}\fi}
-\def\algin{\par\nobreak{\it \localeinput:\/} }
-\def\algout{\par\nobreak\parindent=0pt{\it localeoutput:\/} }
-\def\alginbreak{\hfil\break\hphantom{\it \localeinput:\/} }
+\def\algin{\par\nobreak{\it \localestr{alg:in}:\/} }
+\def\algout{\par\nobreak\parindent=0pt{\it \localestr{alg:in}:\/} }
+\def\alginbreak{\hfil\break\hphantom{\it \localestr{alg:out}:\/} }
 \def\algalias#1{ (#1)}
 
 % Algorithm name in text or in a formula
diff --git a/ucwmac.tex b/ucwmac.tex
index 758d478..5dd13f2 100644
--- a/ucwmac.tex
+++ b/ucwmac.tex
@@ -293,6 +293,24 @@
 \let\plaintilde=~
 \protected\def~{\plaintilde}
 
+%%% Localization %%%
+
+% Current language
+\def\localelang{en}
+
+% Define a new localized string: \localedef{language}{identifier}{message}
+\def\localedef#1#2{\expandafter\def\csname loc:#1:#2\endcsname}
+
+% Expand a localized string in the current language: \localemsg{identifier}
+\def\localestr#1{%
+	\ifcsname loc:\localelang:#1\endcsname
+		\csname loc:\localelang:#1\endcsname
+	\else
+		\ucwwarn{Localized string #1 not defined in language \localelang}%
+		???%
+	\fi
+}
+
 %%% Epilog %%%
 
 % Let's hide all internal macros
-- 
2.39.2