Note that you can put a newline after the sigil most of the time as well, except for many of the punctuation variables - the parser accepts spaces after the sigil, but not newlines.

I've known for this quite some time, and I tried to make a JAPH with no line being more than one character wide ¹. I haven't succeeded. A quicky attempt I just made (my original tries have been lost in time), run with 'perl -M5.010':

$
_  
= 
q
q  
J  
u
s
t
 
a
n
o
t
h
e
r
 
P
e
r
l
 
H 
a  
c  
k
e
r
q
;
s
s
s
seg&say
[download]

(None of the lines above match /^$/)

¹  To avoid having to write I have this amazing JAPH, but the margin isn't wide enough for it...