111–120 of 131 posts
In general, use vecs until you absolutely can't.
Perhaps there are a few uses for LL's in limited circumstances.
> Linked lists are taught as fundamental data structures in programming courses, but they are more commonly encountered in tech interviews than in real-world projects. I beg to disagree. In kernels, drivers, and embedded systems they are very common.
> Linked lists are taught as fundamental data structures in programming courses, but they are more commonly encountered in tech interviews than in real-world projects. I beg to disagree. In kernels, drivers, and embedded systems they are very common.
Linked lists were heavily used in application software before the appearance of standard libraries and Java, which is when dynamically sizable array-based lists become common. There also wasn't a gap between the performance of linked lists and arrays before CPU became significantly faster than RAM.
Earlier quoted context omitted.
1%
More like 0.01% -- if we consider enterprise programmers, web programmers, and application/game programmers which I'd expect to be the largest groups...
The % who have touched kernel bits, wrote a triangle engine scene renderer, wrote a compiler, touched server metal in production, have worked on ASICs, and can put together ML/AI building blocks shrinks way, way down to a handful of living humans.
Earlier quoted context omitted.
Most people who take data structures courses or perform tech interviews don't end up working on kernels, drivers, or embedded systems though. To me, it sounds like the point being made is that there are a large number of programmers who have learned about linked lists but haven't run into many cases where they needed them in the world world, and I think it's accurate.
You need a linked list to write hello world in any Lisp, though. Seems like the glaring exception to the rule!
Earlier quoted context omitted.
I do want to say that I think the Itanic would have fared way, way better in a post-LLVM world where the importance of smart, optimizing compilers is much more valued and understood and language designers actively work hand-in-hand with compiler devs far more often (with much more significant back-and-forth from hardware manufacturers).
I don't think LLVM is particularly good at optimizing VLIW code. Very good optimizing compilers existed before LLVM. Intel had one specifically for Itanium. It wasn't enough.
It strikes me the bottleneck for this problem isn't Vec or List, it's the serde_json Value type that needs to be used. This is useful for serializing/deserializing values into Rust types but if you're trying to validate JSON against a schema you don't actually need the JSON value data, just the types of the nodes (or more specifically, you only need some of the value data, and probably not much of it, so don't pay fo…
I've seen a lexer/parser scheme that encodes the lexer token type along with the token file location information into a u64 integer, something like struct Token { token_type: u8, type_info: u8, token_start: u32, // offset into the source file. token_len: u16 } It's blazing fast. The lexer/parser can process millions of lines per second. The textual information is included, and the location information is included.
The fewer bytes you can pack data into the more data that you can process per second. Computers may be the most complex machines ever built but the simple fact of having fewer things to touch means you can touch more things in the same amount of time remains true.
Earlier quoted context omitted.
I don't think LLVM is particularly good at optimizing VLIW code. Very good optimizing compilers existed before LLVM. Intel had one specifically for Itanium. It wasn't enough.
Why would llvm be particularly good at optimizing vliw code when there’s no demand for it to be? You can’t believe everything else would remain the same in the hypothetical I posed.
Earlier quoted context omitted.
Most people who take data structures courses or perform tech interviews don't end up working on kernels, drivers, or embedded systems though. To me, it sounds like the point being made is that there are a large number of programmers who have learned about linked lists but haven't run into many cases where they needed them in the world world, and I think it's accurate.
You need a linked list to write hello world in any Lisp, though. Seems like the glaring exception to the rule!
SBCL:
* (defun hello-world () (write-string "hello world"))
HELLO-WORLD
* (disassemble #'hello-world)
; disassembly for HELLO-WORLD
; Size: 36 bytes. Origin: #x100311C85C ; HELLO-WORLD
; 5C: AA0A40F9 LDR R0, [THREAD, #16] ; binding-stack-pointer
; 60: 4A0B00F9 STR R0, [CFP, #16]
; 64: EAFDFF58 LDR R0, #x100311C820 ; "hello world"
; 68: 570080D2 MOVZ NARGS, #2
; 6C: 29EC80D2 MOVZ TMP, #1889
; 70: BE6B69F8 LDR LR, [NULL, TMP] ; WRITE-STRING
; 74: DE130091 ADD LR, LR, #4
; 78: C0031FD6 BR LR
; 7C: E00120D4 BRK #15 ; Invalid argument count trap