> What is the alternative to the DSL with lower cognitive load?
In the test example, writing it directly in the programming language. This will usually lead to code that is more verbose and repetitive, but understanding the first example will be faster.
I think of cognitive load like a line. X is the number of cases you’re working with, Y is cognitive load [0]. For someone who already knows a programming language, the DSL is going to have a higher Y intercept since you have to learn something new before you understand the first case. Hopefully, it’s a shallower slope so as you deal with more cases the upfront cost gets paid back. If you have lots of people dealing with one case or doing it infrequently enough they have to relearn each time, this payoff never happens.
This model extends past DSLs to all abstractions. It’s why people often end up happier with test code that’s less abstract/DRY. The access pattern supports it.
Looking at it this way also explains why a DSL for a non-programmer is more likely to be useful. The intercept can be lower than an actual programming language, so you’re ahead from the start.
[0] It’s really more of a curve, but the line model works conceptually.
In the test example, writing it directly in the programming language. This will usually lead to code that is more verbose and repetitive, but understanding the first example will be faster.
I think of cognitive load like a line. X is the number of cases you’re working with, Y is cognitive load [0]. For someone who already knows a programming language, the DSL is going to have a higher Y intercept since you have to learn something new before you understand the first case. Hopefully, it’s a shallower slope so as you deal with more cases the upfront cost gets paid back. If you have lots of people dealing with one case or doing it infrequently enough they have to relearn each time, this payoff never happens.
This model extends past DSLs to all abstractions. It’s why people often end up happier with test code that’s less abstract/DRY. The access pattern supports it.
Looking at it this way also explains why a DSL for a non-programmer is more likely to be useful. The intercept can be lower than an actual programming language, so you’re ahead from the start.
[0] It’s really more of a curve, but the line model works conceptually.