Mercurial Hosting > luan
diff src/luan/interp/GenericForStmt.java @ 19:a7c13c6017f7
add GenericForStmt
git-svn-id: https://luan-java.googlecode.com/svn/trunk@20 21e917c8-12df-6dd8-5cb6-c86387c605b9
author | fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9> |
---|---|
date | Sun, 02 Dec 2012 10:08:24 +0000 |
parents | |
children | d85510d92eee |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/luan/interp/GenericForStmt.java Sun Dec 02 10:08:24 2012 +0000 @@ -0,0 +1,42 @@ +package luan.interp; + +import luan.Lua; +import luan.LuaState; +import luan.LuaException; +import luan.LuaFunction; + + +final class GenericForStmt implements Stmt { + private final int iVars; + private final int nVars; + private final Expr iterExpr; + private final Stmt block; + + GenericForStmt(int iVars,int nVars,Expr iterExpr,Stmt block) { + this.iVars = iVars; + this.nVars = nVars; + this.iterExpr = iterExpr; + this.block = block; + } + + @Override public void eval(LuaState lua) throws LuaException { + LuaFunction iter = Lua.checkFunction( iterExpr.eval(lua) ); + Object[] stack = lua.stack(); + try { + while(true) { + Object[] vals = iter.call(lua); + if( vals.length==0 || vals[0]==null ) + break; + for( int i=0; i<nVars; i++ ) { + stack[iVars+i] = i < vals.length ? vals[i] : null; + } + block.eval(lua); + } + } finally { + for( int i=iVars; i<iVars+nVars; i++ ) { + stack[i] = null; + } + } + } + +}