Revision e08e7174-7747-44fc-8fc9-a54d15e89bba - Code Golf Stack Exchange

# [PHP], 58 bytes

<!-- language-all: lang-php -->

 while(($a=$argn)[$i++]==$a[$i++]&$r=$i<strlen($a));echo$r;

[Try it online!][TIO-jz005m09]

[PHP]: https://php.net/
[TIO-jz005m09]: https://tio.run/##JYpBCoMwEAC/EmEpBvEFGnrrC7wVD7EuzWLILtlIf98Y2sswAyNB6nyXxk@giH0P3oHP72SfQMOwulZ/u0F2QLOWHDG1zdoJX4EhT7UuSwhEqsb8mLiYfWc@z22LEdEYVRFE74@j674shThpHR8X "PHP – Try It Online"

Input string via `STDIN`, output is `falsey` (`null`) if it is double speak, and `truthy` (`1`) if it is not double speak. ([allowed][1]). Or **[59 bytes][2]** to reverse this.


 [1]: https://codegolf.stackexchange.com/questions/189358/is-it-double-speak#comment453405_189358
 [2]: https://tio.run/##JYpBCoMwEAC/ksBSDFLwrqG3vsCb9BDr0iyG7JJV@vumAS/DDIxEqdNDGr@REnYdBA@hfLJbgPr@5VtddoPigSY9SsLcNudGfEe2UMZa5zlGIlVjLm4b83mua0qIxqiKIIaw78Ng7Y/lIM5a788/