https://en.wikipedia.org/wiki/Programming_paradigm
where an appropriate programming paradigm will help with writing, checking, providing "topic" feature (string, statistics, typsetting & printed page layout, etc)
1st guess on "expression/statement" ->
typical general use imperative programming language comparisons:
https://www.ionos.com/digitalguide/websites/web-development/imperative-programming/
2nd guess "expression/statement" -> special purpose parse generators for creating programming languages: racket, lex, yacc, bison, antlr
https://en.wikipedia.org/wiki/Comparison_of_parser_generators
3rd guess "expression/statement" -> special purpose math/statistics:
https://www.linkedin.com/pulse/r-vs-python-matlab-octave-julia-who-winner-siva-prasad-katru
although apl, latex with math also fit under "math expressions"
4th guess "expression/statement" ->
More as a non-programming counterpoint/example: Computational linguistics : https://www.techtarget.com/searchenterpriseai/definition/computational-linguistics-CL
https://en.wikipedia.org/wiki/Eskimo_words_for_snow
Why would a hot weather desert hermit need a word for snow?
----