exercism/go/say/README.md

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# Say
Write a program that will take a number from 0 to 999,999,999,999 and spell out that number in English.
## Step 1
Handle the basic case of 0 through 99.
If the input to the program is `22`, then the output should be
`'twenty-two'`.
Your program should complain loudly if given a number outside the
blessed range.
Some good test cases for this program are:
- 0
- 14
- 50
- 98
- -1
- 100
### Extension
If you're on a Mac, shell out to Mac OS X's `say` program to talk out
loud.
## Step 2
Implement breaking a number up into chunks of thousands.
So `1234567890` should yield a list like 1, 234, 567, and 890, while the
far simpler `1000` should yield just 1 and 0.
The program must also report any values that are out of range.
## Step 3
Now handle inserting the appropriate scale word between those chunks.
So `1234567890` should yield `'1 billion 234 million 567 thousand 890'`
The program must also report any values that are out of range. It's
fine to stop at "trillion".
## Step 4
Put it all together to get nothing but plain English.
`12345` should give `twelve thousand three hundred forty-five`.
The program must also report any values that are out of range.
### Extensions
Use _and_ (correctly) when spelling out the number in English:
- 14 becomes "fourteen".
- 100 becomes "one hundred".
- 120 becomes "one hundred and twenty".
- 1002 becomes "one thousand and two".
- 1323 becomes "one thousand three hundred and twenty-three".
To run the tests simply run the command `go test` in the exercise directory.
If the test suite contains benchmarks, you can run these with the `-bench`
flag:
go test -bench .
For more detailed info about the Go track see the [help
page](http://exercism.io/languages/go).
## Source
A variation on JavaRanch CattleDrive, exercise 4a [http://www.javaranch.com/say.jsp](http://www.javaranch.com/say.jsp)