ToolShed.Test.ReversibleIO

AUTHOR

Dr. Alistair Ward

DESCRIPTION

• Facilitates testing of custom implementations of Read & Show.
• CAVEAT: it doesn't actually do any IO.

Functions

Predicates

isReversible :: (Eq r, Read r, Show r) => r -> Bool

Checks that composing read & show is equivalent to the identity.

readPrependedWhiteSpace :: (Eq r, Read r, Show r) => r -> Bool

Checks whether read can skip prepended white space; isReversible is a prerequisite.

readTrailingGarbage

Arguments

:: (Eq a, Read a, Show a)

=> (Char -> Bool)

Whether a character of garbage might reasonably be confused with valid data, & therefore should be dropped.

-> a

The datum to be written & read.

-> String

The text to follow the written datum.

-> Bool

Checks whether read both copes with garbage following the valid input-data, & leaves it unchanged.