Implement isinstance

[xarus01]

#121

[codecov-io]

Codecov Report

Merging #122 into master will decrease coverage by 0.11%.
The diff coverage is 4.76%.

@@ Coverage Diff @@## master #122 +/- ##
==========================================
- Coverage 72.85% 72.74% -0.12% 
==========================================
Files 60 60 Lines 11949 11970 +21 ==========================================
+ Hits 8706 8707 +1 - Misses 2709 2729 +20 
Partials 534 534

Impacted Files	Coverage Δ
builtin/builtin.go	77.53% <4.76%> (-2.68%)	⬇️

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[corona10]

Please rebase your branch first :)

[ncw]

I think this basically looks sound :-)

I put some comments inline.

I didn't know isinstance recursively unpacked its args - who would have thought!

[ncw]

This would be more efficently written

var new_args = []py.Object{args[0], class[idx]}

[ncw]

This should say

ifres {
returnres
}

to short circuit the rest of the evaluations shouldn't it?

If you do that you can move the definition of res to here.

[ncw]

Then this can say

returnfalse, nil

[ncw]

You are checking this for every entry in the args - it would be better checked in builtin_isinstance I think.

[ncw]

I think this looks fine now except for the spare debug!

Can you fix that, squash into one commit and force push, then I'll merge - thank you :-)

[corona10]

Thanks for the contribution @xarus01

I left some nit review.
cc @ncw

[ncw]

I think this is looking good now - thank you :-)

Apologies for the delay!

I'll merge it now.