gdb allows setting arbitrary convenience variables:
set $a = "test"
set $b = 3
p $a # => "test"
p $b # => 3
Is there a way to do something similar in radare2? I'd like to be able to e.g.:
set $len = 0x100
px `$len` # => does px 0x100
echo $len # => echos 0x100