Fix Issue 9183 - Add a Nullable.get(x) overload

[RazvanN7]

No description provided.

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Bugzilla references

Auto-close	Bugzilla	Description
✓	9183	Add a Nullable.get(x) overload

[atilaneves]

Nitpick: return isNull ? datum : _value;

[atilaneves]

inout?

[RazvanN7]

I tried, but I get a weird error and I don't understand exactly why :
std/typecons.d(2531): Error: pure function 'std.typecons.Nullable!(VariantN!32LU).Nullable.get' cannot call impure destructor 'std.variant.VariantN!32LU.VariantN.~this'

[wilzbach]

This could be const as well?

You could get around the impure error by templating get and thus letting the compiler do the work.

[RazvanN7]

how's this?

[JackStouffer]

Looks good, though I would change datum to default to be in line with other libraries/languages.

[RazvanN7]

@JackStouffer default is a keyword in D.

[dnadlinger]

fallback would be less confusing and would actually describe what this does.

[schveiguy]

You need to mark datum as inout as well, or else the return will always be const (because of the inferred type of the ?: expression).

[schveiguy]

Can you change the T to U as it masks the overarching template type from the Nullable struct?

[MetaLang]

My only criticism is that the function name is only passingly related to what it actually does. I Would suggest something more descriptive like getOrElse or getWithDefault; something that signals that datum is a default or fallback value.

[JackStouffer]

@MetaLang I think that problem is partially addressed by this being consistent with the same type of function in Python (and I think Ruby).