func (n *operatorNode) connectable1(t types.Type, dst *port) bool {
if n.op == "==" || n.op == "!=" {
switch underlying(t).(type) {
case *types.Slice, *types.Map, *types.Signature:
// these types are comparable only with nil
other := n.ins[0]
if other == dst {
other = n.ins[1]
}
return len(other.conns) == 0
}
return types.Comparable(t)
}
b, ok := underlying(t).(*types.Basic)
if !ok {
return false
}
i := b.Info
switch n.op {
case "!", "&&", "||":
return i&types.IsBoolean != 0
case "+":
return i&(types.IsString|types.IsNumeric) != 0
case "-", "*", "/":
return i&types.IsNumeric != 0
case "%", "&", "|", "^", "&^", "<<", ">>":
if (n.op == "<<" || n.op == ">>") && dst == n.ins[1] {
return i&types.IsUnsigned != 0
}
return i&types.IsInteger != 0
case "<", "<=", ">", ">=":
return i&types.IsOrdered != 0
}
panic(n.op)
}
func isComparableType(obj types.Object) bool {
switch obj {
case protoPointer, protoArray, protoChan, protoInterface, protoStruct:
return true
}
t, ok := obj.(*types.TypeName)
return ok && t.GetType() != nil && types.Comparable(t.GetType())
}