It's very nicely done, but I'm afraid I don't "get it" with things like this and written out calculators in general. Why would I type out something long like:
It's particularly suited to calculations I'm doing by fetching various numbers from websites, and for the most part it 'composes' by just copypasting a calca into another one.
Basically where the numbers mean something, aren't stable / I don't know them all when I start, but there's no tabular data or significant aggregation going into the question.
I can see this being useful as a narrative document for collaboration. Explaining to someone how a business process might work given x/y/z pricing. Easy to embed the "why" aspects of things but also it autocalcs things so they could play with the numbers and see the change in impact. Some people can "think in spreadsheet" (I'm quite happy there) but that's not the best medium for everyone.
" Alice's food = £30 Bob's food = £25 VAT = 20% Alice's food + Bob's food + VAT "
Rather than just punch (30+25)*1.2 straight into a calculator?