LLMs bring new nature of abstraction – up and sideways

Summary

Like most loudmouths in this field, I've been paying a lot of attention to the role that generative AI systems may play in software development. I think the appearance of LLMs will change software development to a similar degree as the change from assembler to the first high-level programming languages. The further development of languages and frameworks increased our abstraction level and productivity, but didn't have that kind of impact on the nature of programming. LLMs are making that degree of impact, but with the distinction that it isn't just raising the level of abstraction, but also forcing us to consider what it means to program with non-deterministic tools. High-Level Languages (HLLs) introduced a radically new level of abstraction. With assembler I'm thinking about the instruction set of a particular machine. I have to figure out how to do even simple actions by moving data into the right registers to invoke those specific actions. HLLs meant I could now think in terms of sequences of statements, conditionals to choose between alternatives, and iteration to repeatedly apply statements to collections of data values. I can introduce names into many aspects of my code, making it clear what values are supposed to represent. Early languages certainly had their limitations. My first professional programming was in Fortran IV, where “IF” statements didn't have an “ELSE” clause, and I had to remember to name my integer variables so they started with the letters “I” through “N”. Relaxing such restrictions and gaining block structure (“I can have more than one statement after my IF”) made my programming easier (and more fun) but are the same kind of thing. Now I hardly ever write loops, I instinctively pass functions as data - but I'm still talking to the machine in a similar way than I did all those days ago on the Dorset moors with Fortran. Ruby is a far more sophisticated language than Fortran, but it has the same ambiance, in a way that Fortran and PDP-11 mach...