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From: Joe Wolf <joewolf@gmail.com>
Date: Tue, 24 Jan 2017 08:43:13 -0500
Message-ID: <CAOB2ccn_GApsDC1pRFcJrCWG2_isUPMdnvPNt6L-j1TswwSrmA@mail.gmail.com>
Subject: Parrot and the ++ and -- operators
To: dev@groovy.apache.org
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archived-at: Tue, 24 Jan 2017 13:43:27 -0000

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I accidentally discovered that Groovy 2, in contrast to Java, allows you to
apply the ++ and -- operators to the left and right sides of variables
simultaneously.

int i = 0
++i++
assert i == 1

and you can also chain them in a single statement provided you apply parens

int i = 0
((i++)++)++
assert i == 1
++(++(++i))
assert i == 2
++(++(++i++)++)++
assert i == 3

I can understand allowing the chaining syntax, considering that it's
roughly equivalent to next().next().next(), but as far as I reckon, being
able to use these operators in such a way has no practical purpose.

I haven't tried this code with the Groovy 3 parser yet--I was wondering if
it supported the ++ and -- operators similarly.

-Joe

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<div dir=3D"ltr">I accidentally discovered that Groovy 2, in contrast to Ja=
va, allows you to apply the ++ and -- operators to the left and right sides=
 of variables simultaneously.<div><br></div><div>int i =3D 0</div><div>++i+=
+</div><div>assert i =3D=3D 1</div><div><br></div><div>and you can also cha=
in them in a single statement provided you apply parens</div><div><br></div=
><div><div>int i =3D 0</div><div>((i++)++)++</div><div>assert i =3D=3D 1</d=
iv><div>++(++(++i))</div><div>assert i =3D=3D 2</div><div>++(++(++i++)++)++=
</div><div>assert i =3D=3D 3</div></div><div><br></div><div>I can understan=
d allowing the chaining syntax, considering that it&#39;s roughly equivalen=
t to next().next().next(), but as far as I reckon, being able to use these =
operators in such a way has no practical purpose.</div><div><br></div><div>=
I haven&#39;t tried this code with the Groovy 3 parser yet--I was wondering=
 if it supported the ++ and -- operators similarly.</div><div><br></div><di=
v>-Joe</div><div><br></div></div>

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