[latexila] Use string.get_prev_char() for Utils.char_is_escaped()

[SÃbastien Wilmet <swilmet src gnome org>]

commit b8f161dac7906b6f0e775852d98874047c11d683
Author: SÃbastien Wilmet <swilmet src gnome org>
Date:   Wed Jul 18 20:01:12 2012 +0200

    Use string.get_prev_char() for Utils.char_is_escaped()
    
    This requires Vala from git master.

 CMakeLists.txt |    2 +-
 src/utils.vala |   14 +++-----------
 2 files changed, 4 insertions(+), 12 deletions(-)
---
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 338ea07..830bad8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -39,7 +39,7 @@ find_package (Itstool REQUIRED)
 # Vala
 if (BUILD_VALA)
 	set (_vala_main_version "0.18")
-	set (_vala_min_version "0.17.1")
+	set (_vala_min_version "0.17.3.1")
 
 	if (VALAC)
 		message (STATUS "Use custom valac: ${VALAC}")
diff --git a/src/utils.vala b/src/utils.vala
index 7edecee..56337dd 100644
--- a/src/utils.vala
+++ b/src/utils.vala
@@ -38,23 +38,15 @@ namespace Utils
     {
         return_val_if_fail (char_index < text.length, false);
 
-        int index = (int) char_index;
-        if (! string_get_prev_char (text, ref index, null))
-            return false;
-
         bool escaped = false;
-        while (true)
+        int index = (int) char_index;
+        unichar cur_char;
+        while (text.get_prev_char (ref index, out cur_char))
         {
-            unichar cur_char;
-            bool first_char = ! string_get_prev_char (text, ref index, out cur_char);
-
             if (cur_char != '\\')
                 break;
 
             escaped = ! escaped;
-
-            if (first_char)
-                break;
         }
 
         return escaped;