Journal Entry, April 12th to April 19th 2019

Elixir Koans

1. Thu Apr 18

   • Numbers

     • 2 / 2 = 1.0? Division seems to coerce to floats
     • div() returns the divisor or 2, not 2.5. It's an integer
     • rem() returns the remainder or 1, not 0.5. The .5 is dividing the remainder by 2.
     • (2 * 2.0) = 4.0 as the types coerce the result
     • Float.round(1.2) === round(1.2) == false

     • Individual digits builds an array, not count of digits.

       • i.e. Use that fancy peek feature to determine what each method is doing before blindly answering.
     • Remaining unparsable portion counts the space.
     • Integer.parse returns the unparsable part as a string ".2"
     • Float.ciel seems to round > 0 up to the next integer, even 0.25
   • Atoms

   • Tuples

     • List.delete_at is zero-based or more importantly pretty much all these methods are zero based to match array indexes
   • Lists

   • Keyword Lists koan.

     • It's interesting that it's foo: like json but the tuple reads :foo
     • {:foo , "bar"} Needs the space after :foo