<div dir="ltr"><font face="monospace, monospace">I recently came across this type specification </font><div><div>
</div></div><div><font face="monospace, monospace"><br></font></div><div><font face="monospace, monospace">-type index_spec() :: {add, Index, SecondaryKey} | {remove, Index, SecondaryKey}.<br></font></div><div><font face="monospace, monospace"><br></font></div><div><font face="monospace, monospace">* Is this a `type variable', see [1] and how does one interpret it? </font></div><div><font face="monospace, monospace"><br></font></div><div><font face="monospace, monospace">Best,</font></div><div><font face="monospace, monospace">Raghav</font></div><div><font face="monospace, monospace"><br></font></div><div><font face="monospace, monospace">[1] </font><span style="font-family:monospace,monospace"><a href="http://erlang.org/doc/reference_manual/typespec.html">http://erlang.org/doc/reference_manual/typespec.html</a></span></div></div>