Lenses are immensely useful to the Haskell programmer, but suffer from a discovery problem — without enough exposure or experience, it’s hard to know which operator to use in a given situation. This post provides explanations for common lens operators as well as example-driven references for developers just getting started with lenses.

There is prior art for lens-related reading — we’ve pulled together a short list at the bottom of this post, including one from another Urbinite. The Lens Library itself also provides documentation and usage examples, once you know what you’re looking for.


At Urbint, we pride ourselves on maintaining smooth software development tools. A crucial part of those tools is instant access to documentation via search.

This post takes a quick look at the tools we use to accomplish this, for both internal and external documentation, with Dash, Alfred, and a new Elixir package called ExDash.

A deadly doc-tooling combo

Dash is a tool for managing and searching offline documentation. It has integrations with package managers like Hex and GoDoc, making it easy to add whatever packages you use to your local machine, and it automatically keeps your docs up-to-date when those packages themselves are updated.


He moved on when a crowd got on at Delancey

NYC hat
Thick rubber boots
Drawing pad
A few pencils
Marker (noisy)
No hair
Lumpy face
Old man
Artist
Drawing
Subway sitter
Looking across
Stealing shapes
Guessing, mathing
Devil in the details

11:40 am friday, en route, F train, almost to Jay St

He finishes and hands it across to a woman Pulls out another Blank slate Let’s begin Hands dark and dirty Smiles up at me Think he’s drawing me now Keeps looking at me One can dream Fingernails dark and dirty Blue day today, beautiful Overcast and warm My nose drips and sort of tickles The shape comes…


There’s a moment. when you live alone, and it’s late, and you’re thirsty, and all the cups are clean cause you did all the dishes and you don’t feel like getting one out or making it dirty but you just bought some orange juice and orange juice is really for the morning but you want some anyway not a ton, just a little sip and you remember that you live alone, so you can do whatever you want and you open that oj up right then and there and take a sip straight from the bottle it fills you with…


Fall in love, fall in love
Be happy, be happy
(bees, melted, ty segall. at least that’s what it sounds like.)

Sometimes i wonder why i always fall in love in the Fall
is it the cold or the change or the beauty
everything looks good and warm and nice
just when you start to feel cold and alone and hybernate-y
you lose the sunlight and find it in other people

that sounded pretty much right, until a few moments ago when i realized it’s much simpler than that. you fall in love in Fall because it’s part of the…


Sometimes you’re writing and there’s a bright light in your eyes so you can’t really see so you go to adjust the lamp and the whole thing just comes apart in your hand and the white light blinds you and you realize this thing has been broken for years and before that it wasn’t even yours you just wandered into a new york apartment at one point and it was just waiting for you sockets working: one of three pretty good odds for light, really 1 in 3 is a hell of a lot better than 0 for 3 though…


My buddy greg told me this story about his niece
she can’t really talk but she has one phrase down
she can say “I’ll tell you!”
and that’s it

What is she going to tell us?
I’m sure she knows something
It has to be important
The untapped mind, such potential

she’s probably the smartest person in the world right now i’m here talking too much and trying to find words for people i’m wanting to get everyone up off their butts with some itty bitty letters how could that do anything, they don’t even physically exist they’re not even…


The frustrating moment
is having things-to-say hide
just out of reach
behind this big gray amorphous blob that i call DOUBT
and feeling-full-of-shit
and apologizing-constantly
even though your brain is BURSTING with HARD TRUTHS
that the world Begs to hear
and to see
and to touch and taste and squeeze

You’re almost there you’ve done the work the thoughts are alive, and that’s farther than most explorers ever get but suddenly you grab a pen and your mind fills up with wars and conspiracies and market crashes and jen and death and taxes and peanuts and unions and code and…


new york happens in a moment
you haven’t missed it. it’s a long one. if you’re here, you’re in it.
it’s happening to all of us, right now.

i’m here to tell you to go get your goddamn don’t-die-pizza, stat.
before you don’t survive this moment
before you miss the rest of it
before we all ‘remember’ you
before you’re a little drunk and a little hungry

then a little drunker and a little hungrier go get your don’t-die-pizza before you wake up at church avenue before you’re covered in puke and need an angel to pull you off the…


Sleeping sweetly, you are so so sleepy
The world is in peace around you
Just relax, just for a minute
Let it all escape your mind

WARS and DEATH and SEX and TAXES
Should not bother you
Anxious children, Starving children
Just Ignore those children too

Forget your boss and all the work that
Yesterday you were s'posed to do
It doesn't matter, work is meaningless, and
Tomorrow, it will still be there, for you

Remember that nightmare from your childhood? …

Russell Matney

Engineer @Urbint | Writer of Fiction

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