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exercism fetch elm triangle

Triangle

Determine if a triangle is equilateral, isosceles, or scalene.

An equilateral triangle has all three sides the same length.
An isosceles triangle has at least two sides the same length. (It is sometimes specified as having exactly two sides the same length, but for the purposes of this exercise we'll say at least two.)
A scalene triangle has all sides of different lengths.

Note

For a shape to be a triangle at all, all sides have to be of length > 0, and the sum of the lengths of any two sides must be greater than or equal to the length of the third side. See Triangle Inequality.

Dig Deeper

The case where the sum of the lengths of two sides equals that of the third is known as a degenerate triangle - it has zero area and looks like a single line. Feel free to add your own code/tests to check for degenerate triangles.

Elm Installation

Refer to the Exercism help page for Elm installation and learning resources.

Writing the Code

The first time you start an exercise, you'll need to ensure you have the appropriate dependencies installed.

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$ npm install

Execute the tests with:

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$ npm test

Automatically run tests again when you save changes:

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$ npm run watch

As you work your way through the test suite, be sure to remove the skip <| calls from each test until you get them all passing!

Source

The Ruby Koans triangle project, parts 1 & 2 http://rubykoans.com

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.