<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div>I believe this is a type specification indicating that the function seed/1 takes a parameter X1 of type (that's what the :: means) 3-tuple ({A1, A2, A3}) and returns (indicated by the ->) undefined or a random number (whatever ran/0 indicates).</div><div><br></div><div>Notice that A1, A2, A3 are further specified to be integers in the lines below. </div><div><br></div><div><br>Sent from my iPad</div><div><br>On Dec 16, 2012, at 11:35 AM, Rustom Mody <<a href="mailto:rustompmody@gmail.com">rustompmody@gmail.com</a>> wrote:<br><br></div><blockquote type="cite"><div>In <a href="http://www.erlang.org/doc/man/random.html">http://www.erlang.org/doc/man/random.html</a> I see this line:<br><br><span class="bold_code">seed(X1 :: {A1, A2, A3}) -> undefined | <span class="bold_code"><a href="http://www.erlang.org/doc/man/random.html#type-ran">ran()</a></span></span><br>
<br>Whats the '::' ?<br>Also I cant figure out how to read what follows the '->'<br><br>Please note I am not so much interested in the specifics of random numbers as in being able to read the manual!<br>
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