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Comment by kachnuv_ocasek | Hacker News Reader

I'm sorry to break it to you but every single programming language in existence ignores the physical reality of the machine. That's the point of abstractions such as programming languages.

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There are abstractions which build on the inherently stateful nature of computers with their instruction pointers, registers, memory and peripheral devices, and there are abstractions which coerce you into framing any computational problem like a mathematical formalism.

Haskell's abstractions build on the inherently stateful nature of computers – how do you think Haskell compilers do their job?

(Not to mention that Haskell and its base libraries have plenty of abstractions useful also for the programmer to deal with the inherently stateful nature of computers, e.g. the IO type, STM, State (it's in the name!), Channels, etc.)

Yes, this is essentially it. There's a shape to the causal connections in the real machine that must be respected at higher levels of abstraction. In particular, the shape I mean is that basic mechanism of computation where you have a program counter, instructions and data in mutable memory (von Neumann), and a CPU with registers that "starts on the upper left" of memory, and leaves interesting shaped smears behind when it's done.

On top of this machine shape the OS adds a process abstraction, and a method to speak to devices. It is not coincidence that this process shape looks like the machine shape: lines of source correspond to instructions, declared structures correspond to main memory.... And from here we programmers pick a coordinate system and begin to build. But whatever coords we pick the space, the degrees-of-freedom, always the same: as vast as Turing could fathom. The interesting part of coordinate systems is the kinds of shapes you get for the constraints you picked. But Haskell seems to be a coordinate system with some valid constraint ideas (clear division between purity and side-effect, immutability), but an invalid sense of its identity as merely one coordinate system within this larger structure.

I've never had to worry about what's a register in Python, and barely about pointers and memory (those are highly abstracted away, exactly to the same extent as they are in Haskell).

These days even binary instructions ignore the reality of the physical hardware, as far as I know (I make a javascript lol). The output of e.g. assembler is an instruction set for a virtual machine that doesn't exist, that the CPU translates into actual execution. At least on the intel superscalar side, ARM may be a simpler setup.

Also true. Their point is that Haskell's system ignorance goes much deeper than its peers.

I mean yes, it's a higher level language. Python's system ignorance goes deeper than, say, Ada's, which in turn goes deeper than C++'s, which goes deeper than C's, which goes deeper than many of its predecessors, which go higher than x86, which goes deeper than PDP-11, which goes deeper than logic gates, which go deeper than transistors.

But what's the point? Which languages do we reject because they are sufficiently dissimilar to transistors? Should we all start writing code in VHDL?

(jokingly) yes, in Haskell: https://clash-lang.org

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