Cover image for I built a programming language with no symbols, and the hardest part was the word "and"

Nissan

I'm Spanish, and I kept watching people around me try to learn programming
and give up. Not because loops are hard, but because they were learning two
things at once: the concept, and what while even means.

So I built Fal. All words, in Spanish, no symbols at all.

si edad es mayor que 18
    escribe "Puedes pasar"
si no
    escribe "Todavía no"
fin

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It runs in the browser if you want to poke at it:
https://nissanboss.github.io/Fal/

Two things I didn't see coming.

The word "and" nearly broke it

In Fal, y (and) is both the logical AND and the argument separator:

si a y b           # AND
suma con 1 y 2     # separator

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So y was reserved and you couldn't name a variable y. Annoying the
moment you want coordinates. I assumed it was unfixable and moved on.

Then the author of EsJS turned up in a thread and said context should
decide it, not a reserved word list. He was right, and the fix was
embarrassing: as a keyword y is always infix, it always comes after
something. As a name it's always where a value goes. The parser already
knew which one it was looking at.

escribe x y y            # "x AND the variable y"
tipo Punto con x y y     # fields x and y

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Exact decimals were a footnote that became the main feature

A number is an int64 while it fits, an exact rational once decimals show
up, and only falls back to float when there's no exact answer.

escribe 0.1 mas 0.2             # 0.3
escribe (0.1 mas 0.2) es 0.3    # verdadero

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Looks like a party trick. Then I wrote an example that sums 23 expenses
from a CSV: Fal gives 1546.19 and the categories reconcile to the cent.
The same sums in float give 1546.1900000000005, which doesn't reconcile
with its own parts.

Decimal and BigDecimal exist everywhere, I know. The difference is that a
kid adding two prices doesn't have to know they exist.

What it isn't

Nobody's shipping production software in this. Tree-walking interpreter,
about 8x slower than Python, no package ecosystem. It's a ramp. If someone
gets what a loop is here and then moves to Python, that was the point.

Go, ~5800 lines, no dependencies. Source:
https://github.com/NissanBoss/Fal

If you think the y fix has a hole in it, I'd like to hear it.