Oak Programming Language Specification

Syntax

Oak, like Ink, has automatic comma insertion at end of lines. This means if a comma can be inserted at the end of a line, it will automatically be inserted.

program := expr*

expr := literal | identifier |
    assignment |
    propertyAccess |
    unaryExpr | binaryExpr |
    prefixCall | infixCall |
    ifExpr | withExpr |
    block

literal := nullLiteral |
    numberLiteral | stringLiteral | atomLiteral | boolLiteral |
    listLiteral | objectLiteral |
    fnLiterael

nullLiteral := '?'
numberLiteral := \d+ | \d* '.' \d+
stringLiteral := // single quoted string with standard escape sequences + \x00 syntax
atomLiteral := ':' + identifier
boolLiteral := 'true' | 'false'
listLiteral := '[' ( expr ',' )* ']' // last comma optional
objectLiteral := '{' ( expr ':' expr ',' )* '}' // last comma optional
fnLiteral := 'fn' '(' ( identifier ',' )* (identifier '...')? ')' expr

identifier := \w_ (\w\d_?!)* | _

assignment := (
    identifier [':=' '<-'] expr |
    listLiteral [':=' '<-'] expr |
    objectLiteral [':=' '<-'] expr
)

propertyAccess := identifier ('.' identifier)+

unaryExpr := ('!' | '-') expr
binaryExpr := expr (+ - * / % ^ & | > < = >= <= <<) binaryExpr

prefixCall := expr '(' (expr ',')* ')'
infixCall := expr '|>' prefixCall

ifExpr := 'if' expr? '{' ifClause* '}'
ifClause := expr '->' expr ','

withExpr := 'with' prefixCall fnLiteral

block := '{' expr+ '}' | '(' expr* ')'

AST node types

nullLiteral
stringLiteral
numberLiteral
boolLiteral
atomLiteral
listLiteral
objectLiteral
fnLiteral
identifier
assignment
propertyAccess
unaryExpr
binaryExpr
fnCall
ifExpr
block

Language Functions

• import(path): Imports a module located at the specified path.
• string(x): Converts the argument x to a string.
• int(x): Converts the argument x to an integer.
• float(x): Converts the argument x to a floating-point number.
• atom(c): Creates an atom with the specified character c.
• codepoint(c): Returns the Unicode code point of the character c.
• char(n): Converts the Unicode code point n to a character.
• type(x): Returns the type of the argument x.
• len(x): Returns the length of the argument x.
• keys(x): Returns an array of keys of the argument x.

OS Functions

• args(): Returns command-line arguments as an array of strings.
• env(): Returns the environment variables as an object.
• time(): Returns the current time as a float.
• nanotime(): Returns the current time in nanoseconds as an integer.
• exit(code): Exits the program with the specified exit code.
• rand(): Generates a random floating-point number between 0 and 1.
• srand(length): Seeds the random number generator with the specified length.
• wait(duration): Pauses the program execution for the specified duration.
• exec(path, args, stdin): Executes a command specified by path with the given args and optional standard input stdin. Returns stdout, stderr, and end events.

I/O Interfaces

• input(): Reads input from the standard input.
• print(): Writes output to the standard output.
• ls(path): Lists files and directories in the specified path.
• mkdir(path): Creates a directory at the specified path.
• rm(path): Removes the file or directory at the specified path.
• stat(path): Retrieves file or directory information at the specified path.
• open(path, flags, perm): Opens a file at the specified path with the given flags and permissions.
• close(fd): Closes the file descriptor fd.
• read(fd, offset, length): Reads data from the file descriptor fd starting at the specified offset and reading length bytes.
• write(fd, offset, data): Writes data to the file descriptor fd starting at the specified offset.
• close := listen(host, handler): Listens for incoming connections on the specified host and handles them with the provided handler function.
• req(data): Sends an HTTP request with the provided data.

`go // Req syntax: // ---
req({ url: '' method: 'GET' headers: {} body: _ }) `

Math Functions

• Trigonometric functions
  • sin(n): Calculates the sine of the angle n.
  • cos(n): Calculates the cosine of the angle n.
  • tan(n): Calculates the tangent of the angle n.
• Inverse Trigonometric functions
  • asin(n): Calculates the arcsine of the value n.
  • acos(n): Calculates the arccosine of the value n.
  • atan(n): Calculates the arctangent of the value n.
• Power and logarithmic functions
  • pow(b, n): Raises the base b to the power of n.
  • log(b, n): Calculates the logarithm of n with base b.