ljr/wcmtools/s2/danga/s2/NodeProduct.java

90 lines
2.0 KiB
Java
Executable File

package danga.s2;
public class NodeProduct extends Node
{
Node lhs;
TokenPunct op;
Node rhs;
public static boolean canStart (Tokenizer toker) throws Exception
{
return NodeUnaryExpr.canStart(toker);
}
public static Node parse (Tokenizer toker) throws Exception
{
Node lhs = NodeUnaryExpr.parse(toker);
while (toker.peek().equals(TokenPunct.MULT) ||
toker.peek().equals(TokenPunct.DIV) ||
toker.peek().equals(TokenPunct.MOD)) {
lhs = parseAnother(toker, lhs);
}
return lhs;
}
private static Node parseAnother (Tokenizer toker, Node lhs) throws Exception
{
NodeProduct n = new NodeProduct();
n.lhs = lhs;
n.addNode(n.lhs);
n.op = (TokenPunct) toker.peek();
n.eatToken(toker);
n.skipWhite(toker);
n.rhs = NodeUnaryExpr.parse(toker);
n.addNode(n.rhs);
n.skipWhite(toker);
return n;
}
public Type getType (Checker ck) throws Exception
{
Type lt = lhs.getType(ck);
Type rt = rhs.getType(ck);
if (! rt.equals(Type.INT)) {
throw new Exception("Right hand side of " + op.getPunct() + " operator is not an integer at "+
rhs.getFilePos());
}
if (! lt.equals(Type.INT)) {
throw new Exception("Left hand side of " + op.getPunct() + " operator is not an integer at "+
lhs.getFilePos());
}
return Type.INT;
}
public void asS2 (Indenter o)
{
BackendS2.LParen(o);
lhs.asS2(o);
if (op != null) {
o.write(" " + op.getPunct() + " ");
rhs.asS2(o);
}
BackendS2.RParen(o);
}
public void asPerl (BackendPerl bp, Indenter o)
{
if (op == TokenPunct.DIV)
o.write("int(");
lhs.asPerl(bp, o);
if (op != null) {
if (op == TokenPunct.MULT)
o.write(" * ");
else if (op == TokenPunct.DIV)
o.write(" / ");
else if (op == TokenPunct.MOD)
o.write(" % ");
rhs.asPerl(bp, o);
if (op == TokenPunct.DIV)
o.write(")");
}
}
}