// Binop 
class BinOpTest {
    Null foo() {
        Int x1 = 2;
        Int x2 = 3;
        Null z = null;
        k + x2; // 1/4 failure of clause 1 (nonexistent ident)
        x1 + l; // 2/4 failure of clause 2 (nonexistent ident)
        z + x2; // 3/4 failure of clause 1 (type of ident not Int)
        x1 + z; // 4/4 failure of clause 2 (type of ident not Int)
        x1 + x2; // success
    }
}

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