Standard Library

Built-in functions are called like any function. Those that produce a value are used inside expressions; the others are statements. The complete table with argument lists is in the Built-in Functions reference.

Console

print(value), println(value), inputInt(), inputStr(), see Input & Output.

Conversion

n = str2int('42')        # 42
f = str2float('3.5')     # 3.5
s = int2str(42)          # '42'
t = float2str(3.5)       # '3.500000'

• str2int stops the program with Function error if the text is not an integer (str2int('abc')).
• str2float returns 0 for text that is not a number.
• int2str needs an integer; a float argument is a Function error.
• float2str accepts an integer or a float.

Strings

strlen('hello')                  # 5
substr('hello world', 6, 5)      # 'world'   (text, start, length)
strfind('hello world', 'world')  # 6, or -1 when absent
strcase('Hello', 1)              # 'HELLO'   (non-zero: upper, 0: lower)
trim('  hi  ')                   # 'hi'

substr returns an empty string when start is past the end.

Random numbers

randomSeed(42)
r = random()             # float in [0, 1)
dice = randomRange(1, 6) # integer from 1 to 6, inclusive

Files

assertCapability('FS')
h = openFile('log.txt')
writeFile('line one\n', h)
writeFile('line two\n', h)
println(readFile(h))
closeFile(h)

• openFile(path) opens the file for reading and writing, creating it if it does not exist. Existing contents are kept. It returns a handle.
• writeFile(text, handle) appends text to the end of the file and flushes it.
• readFile(handle) returns the whole file, from the start.
• closeFile(handle) closes the handle. Always close files you open.

HTTP

assertCapability('HTTP')
body = ''
status = httpRequest('GET', 'http://example.com/', '', '', &body)
println(status)
println(body)

httpRequest(method, url, headers, body, &response):

• method is GET, POST, PUT or DELETE.
• headers is a string of Name: value lines separated by \n (empty for none). A Content-Type header sets the type of the request body.
• body is the request body (empty for GET).
• &response is a reference to the variable that receives the response body.
• It returns the HTTP status code, or -1 if the request could not be made, in which case the response variable holds an error message.

Capabilities

assertCapability(name), see Capabilities.

Errors

If a built-in cannot do its job (wrong argument type, unknown handle…), the program prints Function error followed by a message and stops.