When languages are consistent, they are much easier to learn. Spanish is fabulously regular, which helps many people learn it.
When a second language is similar to your native tongue, it is much easier. Swedish speakers have very little trouble learning Danish, but Turkish is a bunch harder, and Korean is _very_ tough.
My point here is that your example is difficult because it lacks any larger context. If you want your API to be easy to learn for Lispers, then s-expressions are going to be better. If the rest of your API uses verbs like "make-a-box" and "paint-the-background", then "make-a-line" is probably the right fit.
Design always works this way: it is defined by its users and its context. When you hit trouble like this, step back.
When a second language is similar to your native tongue, it is much easier. Swedish speakers have very little trouble learning Danish, but Turkish is a bunch harder, and Korean is _very_ tough.
My point here is that your example is difficult because it lacks any larger context. If you want your API to be easy to learn for Lispers, then s-expressions are going to be better. If the rest of your API uses verbs like "make-a-box" and "paint-the-background", then "make-a-line" is probably the right fit.
Design always works this way: it is defined by its users and its context. When you hit trouble like this, step back.