Constants (consts) are even like variables, but one thing is different in constants, Constant value cannot be changed.
for example:
# declare the const
$&name = 'the value'
println($&name)output:
the value
To declare consts, you only need to put a & in the name of variable(location of that is not important).
$&const1 = 123
$&const2 = 'fsgdf'
# ...When we try to change value of the const, we will get error:
$&name = 'the name'
$&name = 'new value'output:
ConstError: "$&name" is const and cannot be changed...
also you can declare a constant, but set value of that later.
for example:
$&name # only declare constant, default value is `None`
# set value
$&name = 'parsa'
println($&name)output:
parsa
But in the second time, error will be raised.