Attempt to define the VarInfo interface

[phipsgabler]

Mostly the dictionary part of it. I am strongly leaning to adopting the Dictionaries.jl way.

[codecov]

Codecov Report

Merging #36 (6ad74af) into main (f9fa387) will decrease coverage by 5.27%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main      #36      +/-   ##
==========================================
- Coverage   83.05%   77.77%   -5.28%     
==========================================
  Files           1        1              
  Lines          59      108      +49     
==========================================
+ Hits           49       84      +35     
- Misses         10       24      +14     

Impacted Files	Coverage Δ
src/varname.jl	77.77% <0.00%> (-5.28%)	⬇️

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[phipsgabler]

Maybe do this by more lenses?

vi[meta(@varname(x[1]), "bla")] == false

where meta(...) constructs a lens specially made for metadata.

[phipsgabler]

OTOH, @yebai, this (or rather, the "defaulting" behaviour of the original varname) would violate a lens invariant we'd like to have:

vi[vn ∘ meta(:bla)] != get(vi[vn], meta(:bla))

[coveralls]

Pull Request Test Coverage Report for Build 1353658861

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 77.778%

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Totals
Change from base Build 1217811956:	0.0%
Covered Lines:	84
Relevant Lines:	108

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💛 - Coveralls