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    <ol> <li>limit is not an array method</li> <li>take requires an argument; it returns an empty array if the array is empty.</li> <li>first can be called without an argument; it returns nil if the array is empty and the argument is absent.</li> </ol> <p>Source for 2.0 take</p> <pre><code> static VALUE rb_ary_take(VALUE obj, VALUE n) { long len = NUM2LONG(n); if (len &lt; 0) { rb_raise(rb_eArgError, "attempt to take negative size"); } return rb_ary_subseq(obj, 0, len); } </code></pre> <p>Source for 2.0 first:</p> <pre><code> static VALUE rb_ary_first(int argc, VALUE *argv, VALUE ary) { if (argc == 0) { if (RARRAY_LEN(ary) == 0) return Qnil; return RARRAY_PTR(ary)[0]; } else { return ary_take_first_or_last(argc, argv, ary, ARY_TAKE_FIRST); } } </code></pre> <hr> <p>In terms of Rails:</p> <ol> <li><p><code>limit(5)</code> will add the scope of <code>limit(5)</code> to an <code>ActiveRecord::Relation</code>. <strong>It can not be called on an array</strong>, so <code>limit(5).limit(4)</code> will fail.</p></li> <li><p><code>first(5)</code> will add the scope of <code>limit(5)</code> to an <code>ActiveRecord::Relation</code>. <strong>It can also be called on an array</strong> so <code>.first(4).first(3)</code> will be the same as <code>.limit(4).first(3)</code>.</p></li> <li><p><code>take(5)</code> will run the query in the current scope, build all the objects and return the first 5. <strong>It only works on arrays</strong>, so <code>Model.take(5)</code> will not work, though the other two will work.</p></li> </ol>
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    1. COAre you sure `#limit` is not an array method? I applied it to a view on an object array `@objects` and it performed the same task as `#take` and `#first`. `#first` can take an argument (optional). Try it yourself
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    2. COYes, see edits in terms of rails.
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