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Functions
Meta
${\mathfrak D}_\mathbb{\to}$
Discussion
Caution 1: Man function definitions are implicit, sometimes secretly so. E.g. defining $f(x):=\sum_{n=0}^infty\frac{(-1)^{3n}}{n!}z^n$ is defining $f(x):=\lim_{m\to\infty}\sum_{n=0}^m\frac{(-1)^{3n}}{n!}z^n$ and a Limit definition is always a Task to find said limit.
Caution 2: In the function Definition, the domain of the function, as well as variables in context, are stated quite broadly - it must be checked if the to-be-function would return a value for any given input.
In that sense, “Functions” really is “Partial functions”, a priori, although I try to state good valid domains on AoC.
todo
Is there any reason to generalize $\to$ to $\prod$ here? I.e. going from $A\to{B}$ (function type) to $\prod_{a:A}B(a)$ (dependent product type).