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> C doesn't let you write "string x = y" because it doesn't have string as a primitive variable type; that's the whole and only reason. But why does C not have

> C doesn't let you write "string x = y" because it doesn't have string as a primitive variable type; that's the whole and only reason. But why does C not have string as a primitive variable type? It's for exactly the reason you state: there are very different approaches a high-level language can take wrt. string ownership/mutability. These approaches might require GC, refcounting, allocation, O(n) copies, etc -- operations that do not trivially map to assembly language. C is close to the machine precisely because it declines to implement any high-level semantics like these.

fixermark 8y ago
I wouldn't call "lacks a feature" the same as "close to the machine" any more than I'd call "specifically refrains from defining whether 'a' or 'b' is first evaluated in an expression like 'a - b'" as "close to the machine." Machines lack statements and expressions entirely, but C has those; the reason that C refrains from being explicit on order of evaluation for (-) and other operators is that on some machines, evaluating b first, then a, then difference, lets you save a couple of assembly instructions at compile-time, and on some other machines, the reverse is true. So C's ambiguity lets the compiler generate code that is that much faster or terser on both machines (at the cost of, well, being Goddamn ambiguous and putting the mental burden of that ambiguity on the programmer ;) ). Perhaps it is more correct to say not that C is "closer to the machine," but that C "tries to position itself as somewhat equidistant from many machines and therefore has design quirks that are dictated by the hardware quirks of several dozen PDP-esque assembly architectures it's trying to span." Quite a few of C's quirks could go away entirely if someone came along, waved a magic wand, and re-wrote history to make K&R C a language targeted exclusively at compiling Intel-based x86 assembly computer achitectures, or even one specific CPU.

fixermark 8y ago

I wouldn't call "lacks a feature" the same as "close to the machine" any more than I'd call "specifically refrains from defining whether 'a' or 'b' is first evaluated in an expression like 'a - b'" as "close to the machine." Machines lack statements and expressions entirely, but C has those; the reason that C refrains from being explicit on order of evaluation for (-) and other operators is that on some machines, evaluating b first, then a, then difference, lets you save a couple of assembly instructions at compile-time, and on some other machines, the reverse is true. So C's ambiguity lets the compiler generate code that is that much faster or terser on both machines (at the cost of, well, being Goddamn ambiguous and putting the mental burden of that ambiguity on the programmer ;) ). Perhaps it is more correct to say not that C is "closer to the machine," but that C "tries to position itself as somewhat equidistant from many machines and therefore has design quirks that are dictated by the hardware quirks of several dozen PDP-esque assembly architectures it's trying to span." Quite a few of C's quirks could go away entirely if someone came along, waved a magic wand, and re-wrote history to make K&R C a language targeted exclusively at compiling Intel-based x86 assembly computer achitectures, or even one specific CPU.