eng-lish

A compiled programming language that reads like English.

Write code the way you think — in plain, readable sentences. No symbols to memorize, no syntax to look up. eng-lish compiles to native machine code via LLVM, so it's readable and fast.

let message be a text with value "Hello, World!".
output message.

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Try it without installing anything

Opens VS Code in your browser with the compiler and the playground ready to go — write a program, press Run, see the output. Nothing is installed on your machine.

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Installation

Prerequisites

• Rust (1.85+, for edition 2024)
• LLVM 21.1 exactly — brew install llvm@21 on macOS, then set LLVM_SYS_211_PREFIX
• Clang (for linking)

LLVM 22 and LLVM 20 will not work: inkwell is pinned to one LLVM major version. See CONTRIBUTING.md for the full setup.

Build from source

git clone https://github.com/Coder8124/eng-lish.git
cd eng-lish
cargo install --path .

Compile and run

englishc examples/hello.eng
./examples/binaries/hello

Print LLVM IR (for debugging)

englishc examples/hello.eng --ir

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Quick Tour

Variables

let name be a text with value "Alice".
let age be a standard number with value 30.
let height be a decimal with value 5.9.
let isStudent be a boolean with value true.

Types:

eng-lish	Description
standard number	64-bit integer
decimal	64-bit float
text	String
boolean	true / false
list of <type>	Typed array

Arithmetic

Infix operators (use in any expression):

let area be a standard number with value width * height.
let average be a decimal with value total / count.
let distance be a standard number with value end - start.
let total be a standard number with value price + tax.

Compound assignment (modifies a variable in place):

let x be a standard number with value 10.

Add 5 to x.        Note: x = x + 5
Subtract 2 from x. Note: x = x - 2
Multiply x by 3.   Note: x = x * 3
Divide x by 4.     Note: x = x / 4

Remainder and quotient:

output the remainder of x divided by 3.
output the quotient of x divided by 3.

Comments

Note: this is a comment — it is ignored by the compiler.
output "Hello!". Note: inline comment after a statement.

Output and Input

output "Enter your name:".
let name be a text with value the result of readLine.
output "Hello, ".
output name.

Control Flow

If/otherwise — requires End. to close:

let score be a standard number with value 85.

If score is greater than 90 then
    output "A".
otherwise if score is greater than 80 then
    output "B".
otherwise if score is greater than 70 then
    output "C".
otherwise
    output "F".
End.

Multiple statements per branch are supported:

If score is greater than 90 then
    output "Great job!".
    output "You got an A.".
otherwise
    output "Keep practicing.".
End.

For loop:

For each i from 1 to 10,
    output i.
End.

While loop:

let count be a standard number with value 0.
While count is less than 5,
    output count.
    Add 1 to count.
End.

Break and continue:

For each i from 1 to 100,
    If the remainder of i divided by 2 is equal to 0 then
        skip.
    End.
    If i is greater than 9 then
        stop.
    End.
    output i.
End.

Functions

To double with a standard number x returning a standard number:
    let doubled be a standard number with value x * 2.
    Give back doubled.
End.

let answer be a standard number with value the result of double with 21.
output answer.

Functions with no return value use returning nothing:

To greet with a text name returning nothing:
    output "Hello, ".
    output name.
End.

Call greet with "World".

Classes

Define a kind called Counter with the following:
    Property count is a standard number.

    To create with a standard number initial:
        Set count to initial.
    End create.

    To increment returning nothing:
        Add 1 to count.
    End.

    To getValue returning a standard number:
        Give back count.
    End.
End kind.

let c be a Counter created with 0.
Ask c to increment.
Ask c to increment.
output the result of asking c to getValue.

Lists

let numbers be a list of standard number with value [10, 20, 30, 40, 50].

output numbers[0].
output numbers[2].

let size be a standard number with value the result of arrayLength with numbers.
let extended be a list of standard number with value the result of append with numbers and 60.
let flipped be a list of standard number with value the result of reverse with numbers.

File I/O

let ok be a boolean with value the result of writeFile with "notes.txt" and "Buy milk.".

If ok then
    output "Saved!".
    let contents be a text with value the result of readFile with "notes.txt".
    output contents.
otherwise
    output "Could not save file.".
End.

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Beginner Mode

Add use beginner. at the top of your program to enable a friendlier experience for new programmers:

• Function calls use a simpler name of arg syntax instead of the result of name with arg
• Error messages say Oops! Line 5 has a problem... instead of compiler jargon
• Type inference relaxes in several places

use beginner.

output "What is your name?".
let name be a text with value the result of readLine.
output combine of "Hello, " and name.

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Data Science

eng-lish has built-in support for statistics, machine learning, and charting — without leaving the language.

Plotting

use "numeric".

let data be a list of decimal with value [2.0, 4.0, 8.0, 16.0, 32.0].
plot data as a line chart titled "Growth" to "chart.html".

Supported chart types: line chart, bar chart, scatter plot, histogram.

Neural Networks

use "neural".

let w1 be a list of decimal with value the result of initWeights with 2 and 4.
let b1 be a list of decimal with value the result of initBiases with 4.
let input be a list of decimal with value [0.5, 0.8].

let hidden be a list of decimal with value the result of linearLayer with w1 and b1 and input and 4 and 2.
let hiddenOut be a list of decimal with value the result of sigmoidActivation with hidden.

See packages/neural/README.md for the full API.

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Standard Library

Math

Function	Description
squareRoot	Square root
absoluteValue	Absolute value
power	Exponentiation
floor / ceiling / round	Rounding
sine / cosine / tangent	Trig
naturalLog / logarithm / exponential	Logarithms
minimum / maximum	Min/max of two values
random	Random decimal 0.0–1.0
randomBetween	Random integer in a range

Text

Function	Description
lengthOf	String length
combine	Concatenate two strings
characterAt	Character at index
uppercase / lowercase	Case conversion
contains	Substring check

Escape sequences in strings: \", \n, \t, \\.

Input / Output

Function	Description
readLine	Read a line of text from stdin
readNumber	Read an integer from stdin
readFile	Read entire file as text
writeFile	Write text to a file
sleep	Pause for N milliseconds

Conversion

Function	Description
textToNumber	Parse integer from text
textToDecimal	Parse decimal from text
numberToText	Integer to text
decimalToText	Decimal to text

Arrays

Function	Description
zeros / ones	Create float array of zeros or ones
range	Create integer range array
arrayLength / vectorLength	Length of an int or float array
sum / mean	Aggregate a float array
arrayMin / arrayMax	Min/max of a float array
append / reverse	Manipulate arrays
standardDeviation / variance	Statistics
correlation	Pearson correlation
fitLine / predictLinear	Linear regression

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Packages

eng-lish has a built-in package manager. Packages are .eng files — just functions and classes your program can use.

Using a package

use "numeric".

output the result of factorial with 10.
output the result of fibonacci with 15.
output the result of isPrime with 17.

Installing a package from GitHub

englishc install https://github.com/user/eng-lish-somepackage

Clones the repo into ~/.eng-lish/packages/. After that, use "somepackage". resolves automatically.

Bundled packages

Package	What it provides
numeric	factorial, fibonacci, gcd, lcm, isPrime, sumUpTo
algorithm	clamp, linearSearch, countOccurrences, maxIndex, minIndex
geometry	distance, hypotenuse, circleArea, triangleArea, degreesToRadians, Point class
math	sign, absoluteInt, isEven, isOdd, digitCount, intPow
strings	repeat, padLeft, padRight, isEmpty
neural	initWeights, initBiases, linearLayer, sigmoidActivation, reluActivation, softmaxActivation, mseError, updateWeights

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Examples

FizzBuzz

For each i from 1 to 100,
    If the remainder of i divided by 15 is equal to 0 then
        output "FizzBuzz".
    otherwise if the remainder of i divided by 3 is equal to 0 then
        output "Fizz".
    otherwise if the remainder of i divided by 5 is equal to 0 then
        output "Buzz".
    otherwise
        output i.
    End.
End.

Guessing Game

let secret be a standard number with value the result of randomBetween with 1 and 100.
let guess be a standard number with value 0.

output "I am thinking of a number between 1 and 100.".

While guess is not equal to secret,
    output "Your guess:".
    Set guess to the result of readNumber.

    If guess is less than secret then
        output "Too low!".
    otherwise if guess is greater than secret then
        output "Too high!".
    otherwise
        output "Correct!".
    End.
End.

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How It Works

.eng source
    │
    ▼
  Lexer  ──►  Parser  ──►  Semantic Analyzer
                                  │
                                  ▼
 Executable  ◄──  Clang  ◄──  Codegen (LLVM IR)

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Documentation

• Language reference — learn a feature, with examples
• Language specification — exactly what the compiler accepts
• Contributing guide — set up the compiler and send a change

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Contributing

Contributions welcome — start with CONTRIBUTING.md, which lists good first issues.

Areas of interest:

• More packages
• Better error messages
• Language server (LSP) support
• Editor support beyond VS Code (see editors/vscode)

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License

MIT — see LICENSE. You are free to use, modify, and distribute eng-lish, including in your own projects.

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Code should be readable. eng-lish makes it so.