John Lang

Millennia ago, there slept an ancient being of mysterious origin. He awoke, unexpectedly. Looking around he noticed a lack normality and the plain. Not content with this, he decided to venture out to new lands to find a world fit to for his desires. He searched long and hard thinking maybe there was no place for him. But after a long journey he found a place for him. Upon reaching this new world, his first words were, "Hello, World!" (he was quite the optimist). Who was this mysterious man we've been following you may ask. Well... his name was John. John Language. And the first thing he did was create the world's first programming language: John Language.¹ The second thing he did was create the Midwestern United States.

As optimistic as he was, he was just as plain. Thus, John Language is not the most interesting language—quite mundane even. Everyone who knows John knows he's not the inventive type (he would not invent creativity for another thousand years!). But, what he would invent are his signature catchphrases used by many today. The classic phrase 'How you like them apples?' And when the going gets tough he always had words of advice for his followers. As John Language would tell you, "It'll get ya where you need to go!" Another common saying of John's was, "There's no stopping that neck once it gets going." Archaeologists, however, have yet to uncover what he meant by this.

Even though John Language is the original creator of John Lang, this compiler was created by Adi Roitburg, Allen Boyce, Jacob Mendoza, JD Elia, Kyle Matton, and Sam Reitich.

Features

• Static typing!
• Typeless todos and almanacs!
• Real simple syntax. John Language is a simple man. Just git er done!
  • No silly parentheses around conditionals!
  • Assignment using colons!
  • Only one numeric type: the unbounded handful!
  • No complicated switches, ternaries, or enhanced for-loops!
• Some real nice data structures!
• Helpful directions. Those aren't error messages!
• Enthusiasm! Every lines ends with an exclamation point!
• Everything is public and accessible. No gatekeepin' here!

Static Errors

• Type errors - Hold up, these types don't match!
• Declaration errors - Hold your horses, pal! I'm not sure what yer talking bout with this variable thing.
• Function call errors - Can't go about calling someone without a phone!
• Function context errors - We can't get goin' 'cause we never even got there!
• Method call errors - I can't find any sorta method in this here doohickey.
• Return type errors - Woah now, dont go returning nothing.
• Member access errors - I can't find any sorta member like that in this here doohickey.
• Mutability errors - Hey now, don't go trying to change that variable's type.
• Control flow errors - There's no popsicle stand to blow.

Example Programs

Hello World

John Lang	JavaScript
letMeLearnYouSomething("Hello, world")!	console.log("Hello, world!");

Variable Declarations

John Lang	JavaScript
switcheroo x: youBetcha! handful y: 2! switcheroo isPositive: y >= 0! chitchat message: "Eat the rich"!	let x = true; let y = 2; let isPositive = (y >= 0); let chitchat = "Eat the rich";

Function Definitions

John Lang	JavaScript
gitErDone isEven(handful x): switcheroo { betterGetGoin x % 2 == 0! }	function isEven(x) { return x % 2 == 0; }

If-Statements

John Lang	JavaScript
ope x > 50 { betterGetGoin 2! } welp ope x > 25 { betterGetGoin 1! } welp { betterGetGoin 0! }	if (x > 50) { return 2; } else if (x > 25) { return 1; } else { return 0; }

Loops

John Lang	JavaScript
tilTheCowsComeHome handful x: 0, x < 10, x: x + 1 { letMeLearnYouSomething(x)! }	for (var x = 0; x < 10; x++) { console.log(x); }

John Lang	JavaScript
holdMyBeer x < 10 { x: x + 1! }	while (x < 10) { x++; }

Class Definitions

John Lang	JavaScript
doohickey Rectangle { slapTogether(handful h, handful w) { handful height: h! handful width: w! } } Rectangle r: whipUp Rectangle(4.0, 8.0)! letMeLearnYouSomething(r.width)! r.width: 5!	class Rectangle { constructor(height, width) { this.height = height; this.width = width; } } let r = new Rectangle(4.0, 8.0); console.log(r.width); r.width = 5.0;

Data Structures

John Lang	JavaScript
todo fruits: ["apple", "banana"]! almanac fruitPrices: { "apple": 2, "banana": 1 }!	let fruits = ["apple", "banana"]; let almanac = fruitPrices: { "apple": 2, "banana": 1 };

Errors

John Lang	JavaScript
whoopsieDaisy "Well, dontcha know, my muffler was actin' up the other day—musta been that darn weather, eh?—and my wife told me ta just go to a mechanic. But dontcha know, I told her, \"Whoa, whoa, whoa. I can fix 'er!\" Cause, ya know, all those mechanics will charge ya DOUBLE what it's gonna cost ya to fix it on yer own. And so I went down to the hardware store, but wouldn't ya know it, they were closed! So I turned around and went to my parents house (they don't get out much, eh? Ye know all this weather; they just weren't built for it, cause they moved up from down south in Florida, cause that's where my dad worked. Ya know, he moved there when he was forty years old, but by then the kids were outta the house and he and my mum had no problem setting down roots again. But they wanted to be closer to family after he retired so they came back up here to Wayzata, but, eh, wouldn't ya know it, they were used to all that warm weather down there in Florida!). And, just as luck would have it, my pops had a spare muffler in his garage (he was quite the handyman back in his day dontcha know), and he invited me in for a cawfee (you know we always take our cawfee black, eh), and we got to chit-chattin' about the kiddos, and it was real nice. But I had to get going, so I grabbed that muffler, drove on back home (the snow was comin' down like cats and dogs at that point), and fixed up ol' bessie's muffler in a jiffy."!	throw "Well, dontcha know, my muffler was actin' up the other day—musta been that darn weather, eh?—and my wife told me ta just go to a mechanic. But dontcha know, I told her, \"Whoa, whoa, whoa. I can fix 'er!\" Cause, ya know, all those mechanics will charge ya DOUBLE what it's gonna cost ya to fix it on yer own. And so I went down to the hardware store, but wouldn't ya know it, they were closed! So I turned around and went to my parents house (they don't get out much, eh? Ye know all this weather; they just weren't built for it, cause they moved up from down south in Florida, cause that's where my dad worked. Ya know, he moved there when he was forty years old, but by then the kids were outta the house and he and my mum had no problem setting down roots again. But they wanted to be closer to family after he retired so they came back up here to Wayzata, but, eh, wouldn't ya know it, they were used to all that warm weather down there in Florida!). And, just as luck would have it, my pops had a spare muffler in his garage (he was quite the handyman back in his day dontcha know), and he invited me in for a cawfee (you know we always take our cawfee black, eh), and we got to chit-chattin' about the kiddos, and it was real nice. But I had to get going, so I grabbed that muffler, drove on back home (the snow was comin' down like cats and dogs at that point), and fixed up ol' bessie's muffler in a jiffy.";

Types

John Lang	Acolytes
switcheroo	bool
handful	number (unbounded)
chitchat	string

Keyword Reference

Conditionals

John Lang	Acolytes
ope	if
welp ope	else if
welp	else
youBetcha	true
thinkAgainPal	false
nah	not/!

Control Flow

John Lang	Acolytes
betterGetGoin	return
tilTheCowsComeHome	for
holdMyBeer	while
letsBlowThisPopsicleStand	break

Functions

John Lang	Acolytes
gitErDone	function
letMeLearnYouSomething	print

Classes

John Lang	Acolytes
doohickey	class
slapTogether	constructor
whipUp	new
me	self

Data Structures

John Lang	Acolytes
todo	list
almanac	dictionary/map

Error Handling

John Lang	Acolytes
whenPigsFly	check/assert
whoopsieDaisy	throw

Footnotes

1. John Language was retroactively renamed to John Lang by Oracle in 2020. ↩