Lightnews — Scholar-powered news

David Bernheisel

@david.bernheisel.com

1.1K followers 160 following 220 posts

Co-host of the Thinking Eixir Podcast | Behind elixirstream.dev | Principal Architect at DScout | bernheisel.com | Founder of zest.dev (consultancy)

#ElixirLang

Posts Replies Media Videos

David Bernheisel

@david.bernheisel.com

quick tip for #ElixirLang and HEEX HTML string attributes.

Eg, when you need conditional css classes, use lists. LiveView will see it as an iolist. It lends itself to better formatting when it gets long, and you can logically group them. You don't need to interpolate a long string.

Much easier to read:

class={[
# GOOD
"block w-full rounded-md py-1.5 shadow-xs text-sm leading-6",
"border-0 text-gray-900 ring-1 ring-inset ring-gray-300",
"placeholder:text-gray-400 disabled:bg-slate-50 focus:ring-zinc-400",
@errors != [] && "ring-rose-400 focus:ring-rose-400",
@class
]}

Bad. See how hard this is to read?

class={"block w-full rounded-md py-1.5 shadow-xs text-sm leading-6 border-0 text-gray-900 ring-1 ring-inset ring-gray-300 placeholder:text-gray-400 disabled:bg-slate-50 focus:ring-zinc-400 #{@errors != [] && "ring-rose-400 focus:ring-rose-400"} #{@class}"}

August 15, 2025 at 2:09 PM

David Bernheisel

@david.bernheisel.com

CSS `attr` now supports a type! this eliminates ugly hacks:

- interpolating inline styling
- tailwind helper functions avoiding interpolating part of a class name (though v4 resolve)
- handling in JS

developer.mozilla.org/en-US/docs/W...

developer.chrome.com/blog/advance...

HTML

<div data-rotation="-3">I am
rotated
by -3 degrees</div>
<div data-rotation="2">And I by 2
degrees</div>
<div>And so am I, using the fallback value of 1.5deg</div>

CSS

div {
width: fit-content;
transform-origin: 50% 50%;
rotate: attr(data-rotation deg, 1.5deg);
}

February 17, 2025 at 12:32 PM

David Bernheisel

@david.bernheisel.com

Just want to know the opportunities!

But yeah stateside is looking grim. Moving elsewhere in the country is also an option.

Evidently we are "assessing the threats" of ADHD meds and SSRIs among others, which may code for "banning soon."

www.whitehouse.gov/presidential...

THE WHITE HOUSE
Sec. 5. Initial Assessment and Strategy from the Make America Healthy Again Commission. (a) Make our Children Healthy Again Assessment. Within 100 days of the date of this order, the Commission shall submit to the President, through the Chair and the Executive Director, the Make Our Children Healthy Again Assessment, which shall:
(i) identify and describe childhood chronic disease in America compared to other countries;
(ii) assess the threat that potential over-utilization of medication, certain food ingredients, certain chemicals, and certain other exposures pose to children with respect to chronic inflammation or other established mechanisms of disease, using rigorous and transparent data, including international comparisons;
(ill) assess the prevalence of and threat posed by the prescription of selective serotonin reuptake inhibitors, antipsychotics, mood stabilizers, stimulants, and weight-loss drugs;|

February 16, 2025 at 1:37 PM

David Bernheisel

@david.bernheisel.com

Holy smokes this is awesome, a new debugger for Phoenix LiveView. Think React devtools, but not a chrome extension.

github.com/software-man...

#ElixirLang

February 7, 2025 at 2:37 PM

David Bernheisel

@david.bernheisel.com

It also has some simplified igniter-powered installation scripts. It's super simple now to add Oban to your existing project or start a new Phoenix project with Oban included.
Lastly, a lot of improvements in the UI, telemetry, simplification of how to mount the dashboard

hexdocs.pm/igniter/read...

$mix archive.install hex igniter_new mix igniter.new oban_demo \ --with phx.new \ --with-args="--database postgres" \ --install oban$

January 16, 2025 at 5:35 PM

David Bernheisel

@david.bernheisel.com

@nezteb.net the Elixir feed doesn't seem to be working. Is the provider of it down?

iirc it was skyfeed, right?

Status page of skyfees indicating all the things are down

January 14, 2025 at 1:15 AM

David Bernheisel

@david.bernheisel.com

AWESOME! Coming in ex_doc soon is a new button to go to the latest version's documentation if you happen to be on an earlier version.

I often find myself googling something, getting a hexdocs.pm link but for some inexplicable reason it puts me into an old version of it

github.com/elixir-lang/...

screenshot of hexdocs for req that contains a link to go to the latest version of the documentation.

January 10, 2025 at 5:54 PM

David Bernheisel

@david.bernheisel.com

Elixir 1.19 lands some new type checking, this time with protocols! If you implement a pattern-match inside of a protocol implementation that isn't possible, the compiler will now warn! It was also warn if you implement for an unknown (eg, misspelled) module.

#ElixirLang

defprotocol UnknownImplFor do
def foo(data)
end

defimpl UnknownImplFor,
for: [
Map,
# Unknown # <-- This is the problem
] do
def foo(data), do: data
end

# Compiling 1 file (.ex)
# warning: you are implementing a protocol for Unknown
# but said module is not available. Make sure the module
# name is correct. If Unknown is an optional dependency,
# please wrap the protocol implementation in a
# Code.ensure_loaded?(Unknown) check
# │
# 5 │ defimpl UnknownImplFor,
# │ ~~~~~~~~~~~~~~~~~~~~~~~
# │
# └─ lib/protocol_types.ex:5: (file)

$defprotocol IncorrectImpl do def foo(data) end defimpl IncorrectImpl, for: [Map, Range, Bitstring] do def foo(nil), do: nil # <--- This is the problem def foo(map), do: map end # Compiling 2 files (.ex) # warning: the 1st pattern in clause will never match: # # nil # # because it is expected to receive type: # # dynamic(%Range{first: term(), last: term(), step: term()}) # # typing violation found at: # │ # 6 │ def foo(nil), do: nil # │ ~~~~~~~~~~~~~~~~~~~~~ # │ # └─ lib/incorrect_dispatch.ex:6: IncorrectDispatch.Range.foo/1$

December 28, 2024 at 3:40 PM

David Bernheisel

@david.bernheisel.com

Set him up for success with stories about "this is how you remind me of what I am really am" and how you "never made it as a wise man" then tell him to look at this photograph