trav

@techsavvytravvy

sr software engineer @ crunchyroll 🦀🔪 @ crablang winning the fight against Big Outside™

832 Following4,868 Followers1,395 Posts

Twitch Bluesky

Is this your profile?Claim it and techsavvytravvy.dirty.social is yours.Claim profile

trav@techsavvytravvy· Jul 5

we're live playing d&d come hang out! twitch.tv/ptmhshow

thumbnail for episode 17 of glow in the dark

trav@techsavvytravvy· Jun 14

we're streaming d&d come hang out twitch.tv/ptmhshow

Fantasy title art for Glow in the Dark: The Baraganoon. A large boat with a skull on the front moves across icy water or snow under purple skies, with several illustrated characters standing on deck holding weapons. Snow blows across the scene, and the gold title text fills the top.

trav@techsavvytravvy· Feb 22

bloodbath starts in like 30 mins come watch us die twitch.tv/ptmhshow

Illustration of a posed fighter with glowing yellow eyes holding an oversized spiked sword over their shoulder. The sword has a pink glow along the blade. The character wears green armor pieces on the shoulders, forearms, knees, and shins, a white cape flowing behind, a headband, and a reddish sash over a white skirt-like garment, set against a black background.

trav@techsavvytravvy· Jan 23

this weekend i'll be joining some friends to stream episode 1 of a brand new d&d campaign called Glow in the Dark - it's an original story created by my best friend and dm with fantasy, scifi, and anime/manga influences. come hang out sunday @ 4pm ET! twitch.tv/ptmhshow

Digital painting of a massive ship named 'SS Friendship' engulfed in flames, stranded in a glowing cave. The ship dominates the center of the image, its burning masts illuminating the cave with orange light. The foreground shows a lineup of seven adventurers and a giant boar standing knee-deep in water, facing the burning ship. Each figure has a distinct silhouette: a small figure with a scythe, a red-haired sword wielder, a cloaked mage with long white hair, and others in fantasy attire. The title 'Glow in the Dark: Survivors of Friendship' appears at the top in a stylized font.

trav@techsavvytravvy· Mar 10

lol it's always this

trav@techsavvytravvy· Feb 22

started reading this to my 4yo tonight and she's about it

Cover of 'The Manga Guide to Databases' by Mana Takahashi and Shoko Azuma. The cover features an anime-style illustration of a fairy character in a green outfit holding a wand, with a magical glow effect. Behind her, three girls in princess attire are standing near a large open book containing database tables and SQL queries. A white castle is visible in the background.

trav@techsavvytravvy· Feb 21

💜

High quality meme featuring multiple images of Scorpion from Mortal Kombat in his signature yellow ninja outfit with black mask. The character is shown in different art styles and poses against fiery backgrounds. The images are placed around the letters, similar to how Homer decorated his workplace sign that originally read 'DON'T FORGET: YOU'RE HERE FOREVER' with Maggie's photos in The Simpsons. Text reads 'GET: HERE OVER' with the letter 'O' positioned separately, likely referencing Scorpion's famous 'Get Over Here' catchphrase. The image is framed with black corner dots on a very light pink background.

trav@techsavvytravvy· Feb 1

no the function would return true, causing it to incorrectly be of type 'number' after narrowing with if statement

TypeScript code showing a function isNumber that incorrectly determines if a value is a number by checking if typeof x is 'string'. The function main demonstrates the problem by assigning an unknown type to x and using isNumber in a conditional check. This leads to a faulty type narrowing where x is mistakenly assumed to be a number, causing an error when passed to the square function.

trav@techsavvytravvy· Feb 1

no because it is narrowing it down to the type and only the specified type or the FAIL unique symbol can be returned, otherwise you'll get an error you could of course return some literal value matching the type but that would have to be pretty deliberate

ts code showing that only the right type can be returned

trav@techsavvytravvy· Jan 31

don't even need the deepEquals since the type will be narrowed by returning the FAIL symbol. so if it's not that, it should be our type

TypeScript code defining a generic function createPredicate<T> that enforces an explicit type parameter using a TS error. It uses NoInfer<T> and an alternative failure type S, which extends symbol and is assigned typeof FAIL. The function returns a predicate that checks whether applying f(x) does not return FAIL. Below, a specific predicate isString is created using createPredicate<string>, verifying if a value is a string.

trav@techsavvytravvy· Jan 31

i will say, there are some downsides. deepEqual can obviously get expensive if you're comparing a lot of big objects, and there are some dumb things about narrowing that mean you can't return the input directly

TypeScript code defining a type predicate function isUser using createPredicate<User>. The function checks if an input x is an object, not null, has 'name' and 'age' properties, and that 'name' is a string while 'age' is a number. A comment notes that returning x directly is not allowed because its inferred type is object & Record<'name', unknown> & Record<'age', unknown>. However, explicitly returning an object with name and age properties works.

trav@techsavvytravvy· Jan 31

the initial attempt is fine, but throwing then doing try/catch for each check isn't ideal and the predicate will be inferred for whatever type you return. instead i want the type param to be used explicitly and we'll return a symbol to indicate failure instead of throwing i think it's pretty nice!

TypeScript code defining a generic function createPredicate<T> that enforces explicit type parameters and includes a fallback failure symbol (S extends symbol = typeof FAIL). The function takes a predicate function f and returns a type predicate function. If the predicate returns FAIL, it returns false; otherwise, it checks deep equality. Below, an example use case defines isString, which ensures a value is a string, returning FAIL if not.

trav@techsavvytravvy· Jan 31

so today @shreyascodes.tech had the idea to create an abstraction for predicate functions, and this is what i came up with initially. it works

TypeScript code defining a generic function createPredicate<T> that takes a function f and returns a type predicate function. The function uses deepEquals to verify type correctness inside a try-catch block. Below, an example use case defines isString, a type predicate created using createPredicate<string>, which throws an error if the input is not a string.

trav@techsavvytravvy· Jan 31

so one of things you can do in typescript is create type predicates that allow you to check if an input value is a specific type with return type `x is Foo`. unfortunately there is nothing that helps you make sure the predicate is accurate - as long as it returns a boolean it will pass

TypeScript code defining two type guard functions: isString and isNumber. The isString function correctly checks if x is a string using typeof x === 'string'. However, the isNumber function mistakenly also checks typeof x === 'string', despite its type guard claiming x is a number. A comment next to the mistake reads '// whoops'.

trav@techsavvytravvy· Jan 31

can see it better here

trav@techsavvytravvy· Jan 31

lissajous.ts

trav@techsavvytravvy· Jan 30

truly github.com/Gankra/cargo...

Terminal output showing an error message from attempting to run 'cargo mommy check' on 'bappy-script v0.1.3'. The Rust compiler reports a syntax error at 'src/main.rs:20:6', indicating 'expected one of '!' or '::''. The line in question reads 'mods passes;', with an error underline under 'passes'. The output ends with 'error: could not compile 'bappy-script'' followed by a whimsical message: 'mommy knows her little girl can do b'.

trav@techsavvytravvy· Jan 29

really? i find that usually when it comes to i/o and async ops that my python requires more ceremony and is harder to follow than the equivalent js

Side-by-side comparison of JavaScript and Python asynchronous file processing. The JavaScript example uses 'Promise.all' to concurrently process an array of filenames with 'processFile', handling errors with a catch block. The Python example uses 'asyncio.create_task' to create concurrent tasks for processing files and collects results as tasks complete using 'asyncio.as_completed', handling exceptions with a try-except block.

trav@techsavvytravvy· Jan 29

oh it's nothing special just a wrapper around the defaults. can be overridden

C code defining a custom memory allocator using function pointers. The code includes an 'Allocator' struct with function pointers for allocation, deallocation, and reallocation. A function 'create_allocator' returns an instance of 'Allocator'. A wrapper function 'realloc_wrapper' is defined, and a global allocator 'GLOBAL_ALLOCATOR' is initialized with 'malloc', 'free', and 'realloc_wrapper' as its function pointers. Header guards ensure the code is included only once.

trav@techsavvytravvy· Jan 29

ehhh not really, just that a function is dynamically passed to the parent as an argument

code snippet demonstrating higher order functions in typescript

trav@techsavvytravvy· Jan 29

trav@techsavvytravvy· Jan 29

really like this pattern where the type name is also the namespace name bc i don't have to do something like Result.Result that i see some others do with the `import * as Result` thing tree-shaking could be a concern tho idk