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var assert = require('assert');
var R = require('../source');var eq = require('./shared/eq');

describe('head', function() {
  it('returns the first element of an ordered collection', function() {    eq(R.head([1, 2, 3]), 1);    eq(R.head([2, 3]), 2);    eq(R.head([3]), 3);    eq(R.head([]), undefined);
    eq(R.head('abc'), 'a');    eq(R.head('bc'), 'b');    eq(R.head('c'), 'c');    eq(R.head(''), '');  });
  it('throws if applied to null or undefined', function() {    assert.throws(function() { R.head(null); }, TypeError);    assert.throws(function() { R.head(undefined); }, TypeError);  });
});