Mercurial Hosting > luan

annotate src/luan/interp/LenExpr.java @ 44:57054fa43189

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
implement table lib git-svn-id: https://luan-java.googlecode.com/svn/trunk@45 21e917c8-12df-6dd8-5cb6-c86387c605b9
author fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
date Wed, 26 Dec 2012 23:53:25 +0000
parents e3624b7cd603
children a443637829c1
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
2
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
1 package luan.interp;
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
2
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
3 import luan.Lua;
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
4 import luan.LuaNumber;
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
5 import luan.LuaTable;
35
e51906de0f11 implement metatables
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 31
diff changeset
6 import luan.LuaFunction;
2
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
7 import luan.LuaException;
40
e3624b7cd603 implement stack trace
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 37
diff changeset
8 import luan.LuaSource;
2
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
9
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
10
7
bca8fc5d928b work on expressions
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 3
diff changeset
11 final class LenExpr extends UnaryOpExpr {
2
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
12
40
e3624b7cd603 implement stack trace
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 37
diff changeset
13 LenExpr(LuaSource.Element se,Expr op) {
e3624b7cd603 implement stack trace
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 37
diff changeset
14 super(se,op);
2
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
15 }
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
16
31
5cf15507d77e separate interpreter from interface
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 11
diff changeset
17 @Override public Object eval(LuaStateImpl lua) throws LuaException {
35
e51906de0f11 implement metatables
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 31
diff changeset
18 Object o = op.eval(lua);
e51906de0f11 implement metatables
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 31
diff changeset
19 if( o instanceof String ) {
e51906de0f11 implement metatables
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 31
diff changeset
20 String s = (String)o;
44
57054fa43189 implement table lib
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 40
diff changeset
21 return LuaNumber.of( s.length() );
2
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
22 }
40
e3624b7cd603 implement stack trace
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 37
diff changeset
23 LuaFunction fn = lua.getHandlerFunction(se,"__len",o);
35
e51906de0f11 implement metatables
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 31
diff changeset
24 if( fn != null )
40
e3624b7cd603 implement stack trace
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 37
diff changeset
25 return Lua.first(lua.call(fn,se,"__len",o));
35
e51906de0f11 implement metatables
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 31
diff changeset
26 if( o instanceof LuaTable ) {
e51906de0f11 implement metatables
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 31
diff changeset
27 LuaTable t = (LuaTable)o;
2
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
28 return t.length();
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
29 }
40
e3624b7cd603 implement stack trace
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents: 37
diff changeset
30 throw new LuaException( lua, se, "attempt to get length of a " + Lua.type(o) + " value" );
2
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
31 }
4da26b11d12a start interp
fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
parents:
diff changeset
32 }