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CAFxX / textproto.go
Last active September 26, 2023 01:49
textproto.CanonincalMIMEHeaderKey with memoization and GC
package textproto
import (
// CanonincalMIMEHeaderKey is like textproto.CanonicalMIMEHeaderKey but it
// memoizes results to avoid repeated allocations of the same string.
package maps
type ReadMostlyMap[K comparable, V any] struct {
mu sync.Mutex
m atomic.Pointer // map[K]V
func map2ptr[K comparable, V any](m map[K]V) unsafe.Pointer {
im := any(m)
return *(*unsafe.Pointer)(unsafe.Pointer(&im))
Verifying that I control the following Nostr public key: npub1j67s9mwffj6ue909esy4ldyhte9xheu5nh2lwed2qycqfdmfjmuq40chpa
Last active January 24, 2024 00:11
Go wishlist


Shorthand error definition

Instead of things like var ErrFoo = errors.New("foo") or return fmt.Errorf("foo: %d", n) I would like a shorthand syntax that allows to define a new error type.

Simple error

CAFxX / bulk_insert.go
Last active December 31, 2022 02:39
SQL bulk insert
package bulkinsert
import (
CAFxX / load_data.go
Last active December 29, 2022 06:42
MySQL bulk data loader (via LOAD DATA LOCAL INFILE)
package mysql
import (
package xsync
import "sync"
type TryLocker interface {
sync.Locker // Lock(); Unlock()
TryLock() bool
// LockAndDo will acquire the lock l and execute fn.
CAFxX / batch_getter.go
Last active July 27, 2023 01:42
Request batcher
package batchgetter
type Getter[I, T any] interface {
Get(context.Context, []I) ([]T, error)
type BatchGetter[I, T any] struct {
parent Getter[I, T]
batchWait time.Duration
CAFxX / genOptIface.go
Created November 16, 2022 08:53
Generate objects with optional methods (Golang)
package main
import "fmt"
func genOptIface(name string, opt ...string) {
if len(opt) == 0 {
panic("zero opt types")
if len(opt) > 10 {
panic("too many opt types")
CAFxX / lookup.cpp
Created November 11, 2022 06:10
AVX-512 vectorized associative lookup
#include <immintrin.h>
#include <stdint.h>
int getIndexOf(__m512i const *values, int64_t target)
__m512i valuesSimd = _mm512_loadu_si512(values);
__m512i targetSplatted = _mm512_set1_epi64(target);
__mmask8 equalMask = _mm512_cmpeq_epi64_mask(valuesSimd, targetSplatted);
uint32_t equalMaskInt = _cvtmask8_u32(equalMask);
int index = _tzcnt_u32(equalMaskInt);