-bash: conditional binary expected -bash: syntax error near "--compare-versions"?

Question

bash

if ; then echo true; else echo false; fi

-bash: conditional binary expected
-bash: syntax error near "--compare-versions"
Why?

Answer 1

What are you going to compare here?
is a standalone operator, not a syntax for conditions
. You need it apparently like this:

if dpkg --compare-versions "1.5.2" "lt" "1.2.11"; then echo true; else echo false; fi