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0 pointsfrou_dh11y ago0 comments

In Go, you're not returning a sum type, so it's down to the programmer to remember that the "real" return value is likely toxic waste when its copassenger the error return value is non-nil.

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8 comments · 3 top-level

Karunamon11y ago· 3 in thread

What's the practical problem of this, though? The (varname, err := thing) pattern is sprinkled all throughout the language, enough to where it should be instinctive for a coder to check the err value when doing anything that could fail.

frou_dhOP11y ago

Of course we can put up with anything. The topic of the subthread is that it's halfassed and has a better alternative.

jshen11y ago

A major hit to readability. Every call site where you want to check for an error requires adding another level of nesting.

frou_dhOP11y ago

That's a different issue. Pattern-matching a sum-type value, though safer, would be "noise" too.

jbooth11y ago· 2 in thread

Wait, that's it? The difference between bad (with italics!) and awesome is being able to reference the garbage half of a multiple return?

wting11y ago

You can embed metadata with sum types on a return object. You can then use the metadata programmatically to increase correctness, enhance readability, and reduce boilerplate. This blog post goes into more details:

http://fsharpforfunandprofit.com/posts/recipe-part2/#series-...

frou_dhOP11y ago

I'm not the GP. Ask them for their full story.

4ydx11y ago

Ok thanks for filling in the blank.

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