// param-mutation.slang

// When a parameter is passed to `in`, it is mutable but generates a warning as it probably (?)
// isn't what the programmer intended.

//DIAGNOSTIC_TEST:SIMPLE:

struct MutatingStruct
{
    [mutating] void setValue(int value) { m_value = value; }
    int m_value;
};

int doThing(MutatingStruct s, int v)
{
    // Should generate a warning. 
    s.setValue(v + 1);
    return s.m_value;
}

// For non-copyable types (such as HitObject or NonCopyableStruct declared below), if passed as as `in`
// should produce an error.
// NOTE! This *doesn't* produce an error (or warning) because NonCopyable types are *implicitly* 
// made *ref* when parsed as arguments. 

[__NonCopyableType]
struct NonCopyableStruct
{
    [mutating] void setValue(int value) { m_value = value; }
    int m_value;
};

int doThing2(NonCopyableStruct s, int v)
{
    // Currently doesn't produce an error/warning because NonCopyableStruct is passed as *ref* implicitly.
    s.setValue(v + 1);
    return s.m_value;
}