if and while statements are highlighted as functions when using parenthesized expressions.
This seems to happen for any valid rust identifier.
Discovered this in the demo section of the website.

if (1 + 2) * 2 == 6 {}
if true {}
while (1 + 2) * 2 == 6 {}
while true {}
for (a, b) in (0..10).enumerate() {}
for a in 0..10 {}