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angelikatyborska's solution

to Two Fer in the Erlang Track

Published at Oct 14 2019 · 0 comments
Test suite


This exercise has changed since this solution was written.

Two-fer or 2-fer is short for two for one. One for you and one for me.

Given a name, return a string with the message:

One for X, one for me.

Where X is the given name.

However, if the name is missing, return the string:

One for you, one for me.

Here are some examples:

Name String to return
Alice One for Alice, one for me.
Bob One for Bob, one for me.
One for you, one for me.
Zaphod One for Zaphod, one for me.

Running tests

In order to run the tests, issue the following command from the exercise directory:

For running the tests provided, rebar3 is used as it is the official build and dependency management tool for erlang now. Please refer to the tracks installation instructions on how to do that.

In order to run the tests, you can issue the following command from the exercise directory.

$ rebar3 eunit


For detailed information about the Erlang track, please refer to the help page on the Exercism site. This covers the basic information on setting up the development environment expected by the exercises.



Submitting Incomplete Solutions

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


%% Based on canonical data version 1.2.0-1
%% https://github.com/exercism/problem-specifications/raw/master/exercises/two-fer/canonical-data.json
%% This file is automatically generated from the exercises canonical data.



-define(assertStringEqual(Expect, Expr),
        begin ((fun () ->
            __X = (Expect),
            __Y = (Expr),
            case string:equal(__X, __Y) of
                true -> ok;
                false -> erlang:error({assertStringEqual,
                    [{module, ?MODULE},
                     {line, ?LINE},
                     {expression, (??Expr)},
                     {expected, unicode:characters_to_list(__X)},
                     {value, unicode:characters_to_list(__Y)}]})

-define(_assertStringEqual(Expect, Expr), ?_test(?assertStringEqual(Expect, Expr))).

'1_no_name_given_test_'() ->
    {"no name given",
     ?_assertStringEqual("One for you, one for me.",

'2_a_name_given_test_'() ->
    {"a name given",
     ?_assertStringEqual("One for Alice, one for me.",

'3_another_name_given_test_'() ->
    {"another name given",
     ?_assertStringEqual("One for Bob, one for me.",

-export([two_fer/0, two_fer/1]).

two_fer() -> two_fer("you").

two_fer(Name) -> "One for " ++ Name ++ ", one for me.".

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