Making it easier to work with Optional columns.

[imarios]

case class X(i: Option[Int], j: Option[String])
val t = TypedDataset.create(Seq( X(Some(1), None), X(None, None), X(Some(10), Some("foo"))))
 t.select(t('i).opt.map(_*2), t('j).opt.map(_.startsWith("fo"))).show().run()
+----+----+
|  _1|  _2|
+----+----+
|   2|null|
|null|null|
|  20|true|
+----+----+

[codecov]

Codecov Report

Merging #479 (5f345a8) into master (854d5b6) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #479   +/-   ##
=======================================
  Coverage   96.23%   96.24%           
=======================================
  Files          60       60           
  Lines        1036     1038    +2     
  Branches        7        9    +2     
=======================================
+ Hits          997      999    +2     
  Misses         39       39           

Flag	Coverage Δ
2.12.12	96.24% <100.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
dataset/src/main/scala/frameless/TypedColumn.scala	100.00% <100.00%> (ø)

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[ayoub-benali]

This is a really great improvement, thanks !