Standard Library

DaeDaLus provides a standard library module called Daedalus that can be imported with:

import Daedalus

Multi-Byte Integer Parsers

These parsers read multi-byte integers from the input. They use the implicit parameter ?bigEndian to determine byte order:

There are also variants with a fixed byte order:

Parser	Description
`BEUInt16`, `BEUInt32`, …	Big-endian (most significant byte first)
`LEUInt16`, `LEUInt32`, …	Little-endian (least significant byte first)

Parser	Description
`HalfFloat`	Parse a 16-bit half-precision float
`Float`	Parse a 32-bit single-precision float
`Double`	Parse a 64-bit double-precision float

These also have BE and LE variants (e.g., BEFloat, LEDouble).

Combinator	Description
`Guard b`	Succeed if `b` is true, fail otherwise
`GuardMsg b s`	Like `Guard` but with a custom error message
`When P x`	Parse `P`, discard its result, return `x`
`Default x P`	Parse `P`; if it fails, return `x` instead
`Only P`	Succeed only if `P` consumes all input
`Count P`	Count how many times `P` succeeds
`ManyStart P Q`	Match one `P` followed by zero or more `Q`

Function	Description
`numBase base ds`	Evaluate a digit array in the given base
`min x y`	The smaller of two values
`max x y`	The larger of two values

Combinator	Description
`SetStreamAt n s`	Set the stream to the `n`-th byte of `s`
`Skip n`	Advance the current stream by `n` bytes
`Chunk n P`	Parse the next `n` bytes using `P`
`Bytes n`	Get the next `n` bytes as a raw array
`LookAhead P`	Parse with `P` without consuming input
`WithStream s P`	Parse `s` with `P`, leaving current stream unchanged

These are useful for writing test cases within DaeDaLus:

Combinator	Description
`TestAccepts Parser input`	Succeeds if `Parser` consumes all of `input`
`TestAcceptsPrefix Parser input`	Succeeds if `Parser` accepts a prefix of `input`
`TestParses Parser input expected`	Succeeds if `Parser` produces `expected` from `input`
`TestFails Parser input`	Succeeds if `Parser` rejects `input`