Add Last Documentation
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src/Last/README.md
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| `Last` is a `Monoid` that will always return the last, non-empty value when | ||
| (2) `Last` instances are combined. `Last` is able to be a `Monoid` because | ||
| it implements a `Maybe` under the hood. The use of the `Maybe` allows for an | ||
| [`empty`][#empty] `Last` to be represented with a `Nothing`. |
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[`empty`][#empty] should be [`empty`](#empty)
Note that this is also in First/README.md.
src/Last/README.md
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| `concat` is used to combine (2) `Semigroup`s of the same type under an operation | ||
| specified by the `Semigroup`. In the case of `Last`, it will always provide the | ||
| last non-empty value. Any subsequent non-empty values will be thrown away and |
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Any subsequent non-empty values will be thrown away
Won't subsequent non-empty values actually be kept, so that the last non-empty value will always be the result?
src/Last/README.md
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| const mconcatMap = require('crocks/helpers/mconcatMap') | ||
| const safe = require('crocks/Maybe/safe') | ||
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| // lastString :: [ a ] -> Last String |
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// lastString :: [ a ] -> Last String
should be
// firstString :: [ a ] -> First String
src/Last/README.md
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| const firstString = | ||
| mconcatMap(First, safe(isString)) | ||
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| // unfixFirstString :: [ a ] -> First String |
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// unfixFirstString :: [ a ] -> First String
should be
// unfixFirstString :: [ a ] -> Last String
src/Last/README.md
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| unfixFirstString([ 'one', 2, 'Three', 4 ]) | ||
| .concat(Last('another string')) | ||
| //=> Last( Just "another string" ) |
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Perhaps also show:
unfixFirstString([ 'one', 2, 'Three', 4 ])
//=> Last( Just "one" )
src/Last/README.md
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| lastNumVal({ val: 97 }) | ||
| .concat(Last(80)) | ||
| //=> Last( Just 97 ) |
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Not sure what this example is supposed to be, but the result is incorrect. The following example is exactly the same but has the correct result.
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That should have been switched to:
Last(Just(80))
.concat(lastNumVal({ val: 97 }))
//=> Last( Just 97 )
src/Last/README.md
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| // isEven :: Number -> Boolean | ||
| const isEven = | ||
| x => !(x % 2) |
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While this is a clever way to exploit truthy/falsy values of numbers like0, IMO this could detract from the example because of the boolean thinking required. x % 2 === 0 is usually enough for me. It's not a big deal, though I found myself trying to work out this function instead of the example. Probably because I'm tired, but ¯\(ツ)/¯
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Last but not Least
This is another PR that addresses the
Lastitem on this issue by adding the README for theLastmonoid. It is pretty much the same thing asFirst, but kinda the opposite.Also made some corrections to the
FirstREADME in this PR as well.