Sortable no longer depends on Underscore

[sloria]

• Add simplified implementation of filter and difference
• Use Array.prototype.map instead of _.map
• Use Array.prototype.forEach instead of _.each
• Update docs

[kevinbarabash]

@sloria I think in general it makes sense to remove dependencies so that react-components is more lightweight. I haven't actually used this library, is it possible to require this component on its own?

[sophiebits]

Another thing we could consider is depending on lodash.difference which only pulls in that one function. +1 for builtin map and forEach though.

[sloria]

@spicyj lodash.difference might still be more LOC than it's worth. It includes code to handle different input types and variable arity--the sortable component has just two usages of difference, for which both the input types and arity are always the same.

Another downside is that if you are already using the full lodash package in your project, depending on lodash.difference will add duplicated code to your vendor bundle.

[sophiebits]

Your approach adds duplicated code to your bundle regardless of whether you're using lodash. There's not a practical difference between 10 and 50 lines here and I'm much happier to depend on a well-maintained library like lodash rather than reimplementing things and having the potential for bugs.

[sophiebits]

If we use Array.prototype.filter I guess the one-line difference function here is fine.

[sloria]

@spicyj I originally used Array.prototype.filter, but this breaks because we need to filter a NodeList here, which doesn't implement filter.

[sophiebits]

Did you see my other comment? Array.prototype.filter.call(nodeList, pred) should work fine.

[sloria]

@spicyj Ah, sorry, yeah, just caught your other comment. Yes, that will work; I'll change the code.

[kevinbarabash]

@sloria these changes have been made by another commit. Sorry for not merging this sooner.

[sloria]

@kevinbarabash No problem. Glad to see the change go in.