Add Lazy type

[markuswustenberg]

Lazy is a function that returns a Node that is itself also a Node.

Used with If, it enables lazy evaluation of the node to return, depending on the condition passed to If.

See also #99 for a different approach explored.

[codecov]

Codecov Report

Merging #101 (b6265a1) into master (c868c52) will not change coverage.
The diff coverage is 100.00%.

❗ Current head b6265a1 differs from pull request most recent head 6e4a63f. Consider uploading reports for the commit 6e4a63f to get more accurate results

@@            Coverage Diff            @@
##            master      #101   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
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  Files            9         9           
  Lines          491       493    +2     
=========================================
+ Hits           491       493    +2     

Impacted Files	Coverage Δ
gomponents.go	100.00% <100.00%> (ø)

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[oderwat]

This is a neat trick. I like this kind of lazy evaluation as it also works for if/else and even for something as MaybeString(v *string,func(v string) g.Node)

[markuswustenberg]

Yeah, I think I like this solution too. Useful anywhere where lazy node evaluation could be nice. Maybe I should just call it Lazy.

[markuswustenberg]

Hmm. Sadly this doesn't work for attributes. I'll have to rethink a bit.