Expose some methods on strings to Nasal

src/Scripting/CMakeLists.txt

@@ -7,6 +7,7 @@ set(SOURCES
     NasalCanvas.cxx
     NasalClipboard.cxx
     NasalCondition.cxx
+    NasalString.cxx
 	)
 
 set(HEADERS
@@ -15,6 +16,7 @@ set(HEADERS
     NasalCanvas.hxx
     NasalClipboard.hxx
     NasalCondition.hxx
+    NasalString.hxx
 	)
 
 if(WIN32)

src/Scripting/NasalString.cxx

@@ -0,0 +1,133 @@
+// Add (std::string) like methods to Nasal strings
+//
+// Copyright (C) 2013  Thomas Geymayer <tomgey@gmail.com>
+//
+// This program 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 2 of the
+// License, or (at your option) any later version.
+//
+// This program 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 this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include "NasalString.hxx"
+
+#include <simgear/nasal/cppbind/from_nasal.hxx>
+#include <simgear/nasal/cppbind/Ghost.hxx>
+#include <simgear/nasal/cppbind/NasalHash.hxx>
+#include <simgear/nasal/cppbind/NasalString.hxx>
+
+/**
+ *  Compare (sub)string with other string
+ *
+ *  compare(s)
+ *  compare(pos, len, s)
+ */
+static naRef f_compare(naContext c, naRef me, int argc, naRef* args)
+{
+  nasal::CallContext ctx(c, argc, args);
+  nasal::String str = nasal::from_nasal<nasal::String>(c, me),
+                rhs = ctx.requireArg<nasal::String>(argc > 1 ? 2 : 0);
+  size_t pos = argc > 1 ? ctx.requireArg<int>(1) : 0;
+  size_t len = argc > 1 ? ctx.requireArg<int>(2) : 0;
+
+  if( len == 0 )
+    len = nasal::String::npos;
+
+  return naNum( str.compare(pos, len, rhs) );
+}
+
+/**
+ *  Check whether string starts with other string
+ */
+static naRef f_starts_with(naContext c, naRef me, int argc, naRef* args)
+{
+  nasal::CallContext ctx(c, argc, args);
+  nasal::String str = nasal::from_nasal<nasal::String>(c, me),
+                rhs = ctx.requireArg<nasal::String>(0);
+
+  return naNum( str.starts_with(rhs) );
+}
+
+/**
+ *  Helper to convert size_t position/npos to Nasal conventions (-1 == npos)
+ */
+naRef pos_to_nasal(size_t pos)
+{
+  if( pos == nasal::String::npos )
+    return naNum(-1);
+  else
+    return naNum(pos);
+}
+
+/**
+ *  Find first occurrence of single character
+ *
+ *  find(c, pos = 0)
+ */
+static naRef f_find(naContext c, naRef me, int argc, naRef* args)
+{
+  nasal::CallContext ctx(c, argc, args);
+  nasal::String str = nasal::from_nasal<nasal::String>(c, me),
+                find = ctx.requireArg<nasal::String>(0);
+  size_t pos = ctx.getArg<int>(1, 0);
+
+  if( find.size() != 1 )
+    naRuntimeError(c, "string::find: single character expected");
+
+  return pos_to_nasal( str.find(*find.c_str(), pos) );
+}
+
+/**
+ * Find first character of a string occurring in this string
+ *
+ * find_first_of(search, pos = 0)
+ */
+static naRef f_find_first_of(naContext c, naRef me, int argc, naRef* args)
+{
+  nasal::CallContext ctx(c, argc, args);
+  nasal::String str = nasal::from_nasal<nasal::String>(c, me),
+                find = ctx.requireArg<nasal::String>(0);
+  size_t pos = ctx.getArg<int>(1, 0);
+
+  return pos_to_nasal( str.find_first_of(find, pos) );
+}
+
+/**
+ * Find first character of this string not occurring in the other string
+ *
+ * find_first_not_of(search, pos = 0)
+ */
+static naRef f_find_first_not_of(naContext c, naRef me, int argc, naRef* args)
+{
+  nasal::CallContext ctx(c, argc, args);
+  nasal::String str = nasal::from_nasal<nasal::String>(c, me),
+                find = ctx.requireArg<nasal::String>(0);
+  size_t pos = ctx.getArg<int>(1, 0);
+
+  return pos_to_nasal( str.find_first_not_of(find, pos) );
+}
+
+//------------------------------------------------------------------------------
+naRef initNasalString(naRef globals, naRef string, naContext c, naRef gcSave)
+{
+  nasal::Hash string_module(string, c);
+
+  string_module.set("compare", f_compare);
+  string_module.set("starts_with", f_starts_with);
+  string_module.set("find", f_find);
+  string_module.set("find_first_of", f_find_first_of);
+  string_module.set("find_first_not_of", f_find_first_not_of);
+
+  return naNil();
+}

src/Scripting/NasalString.hxx

@@ -0,0 +1,27 @@
+// Add (std::string) like methods to Nasal strings
+//
+// Copyright (C) 2013  Thomas Geymayer <tomgey@gmail.com>
+//
+// This program 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 2 of the
+// License, or (at your option) any later version.
+//
+// This program 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 this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+#ifndef SCRIPTING_NASAL_STRING_HXX
+#define SCRIPTING_NASAL_STRING_HXX
+
+#include <simgear/nasal/nasal.h>
+
+naRef initNasalString(naRef globals, naRef string, naContext c, naRef gcSave);
+
+#endif // of SCRIPTING_NASAL_STRING_HXX
+

src/Scripting/NasalSys.cxx

@@ -29,6 +29,7 @@
 #include "NasalCanvas.hxx"
 #include "NasalClipboard.hxx"
 #include "NasalCondition.hxx"
+#include "NasalString.hxx"
 
 #include <Main/globals.hxx>
 #include <Main/util.hxx>
@@ -100,6 +101,7 @@ FGNasalSys::FGNasalSys()
     nasalSys = this;
     _context = 0;
     _globals = naNil();
+    _string = naNil();
     _gcHash = naNil();
     _nextGCKey = 0; // Any value will do
     _callCount = 0;
@@ -154,6 +156,7 @@ FGNasalSys::~FGNasalSys()
 
     naFreeContext(_context);
     _globals = naNil();
+    _string = naNil();
 }
 
 bool FGNasalSys::parseAndRun(const char* sourceCode)
@@ -547,8 +550,6 @@ void FGNasalSys::init()
         hashset(_globals, funcs[i].name,
                 naNewFunc(_context, naNewCCode(_context, funcs[i].func)));
 
-
-  
     // And our SGPropertyNode wrapper
     hashset(_globals, "props", genPropsModule());
 
@@ -558,6 +559,11 @@ void FGNasalSys::init()
     _gcHash = naNewHash(_context);
     hashset(_globals, "__gcsave", _gcHash);
 
+    // Add string methods
+    _string = naInit_string(_context);
+    naSave(_context, _string);
+    initNasalString(_globals, _string, _context, _gcHash);
+
     initNasalPositioned(_globals, _context, _gcHash);
     NasalClipboard::init(this);
     initNasalCanvas(_globals, _context, _gcHash);

src/Scripting/NasalSys.hxx

@@ -186,7 +186,8 @@ private:
     naRef genPropsModule();
 
     naContext _context;
-    naRef _globals;
+    naRef _globals,
+          _string;
 
     SGPropertyNode_ptr _cmdArg;