PRXMATCH with string containing ampersand

[PamG]

How do I go about using PRXMATCH to search for a string that contains ampersand ? SAS is assuming that it is a macro variable. 

data have;
input varchar $;
datalines;
ABCDEF
GHI
KLM
KLM&F
KLM&FG
;
run;

data want;set have;
if prxmatch("m/KLM&F/i,varchar) >0; *gives an error Macro variable F not resolved;
run;

[PamG]

Correction: Please note that I missed putting the ending quotation marks after /i.  I cannot edit my post to make the correction.

[Tom · Accepted solution]

Use single quotes so the macro processor will ignore the string.

if prxmatch('m/KLM&F/i',varchar) >0;

[PamG]

Thanks!