Streamly.Unicode.String

Convenient template Haskell quasiquoters to format strings.

The str quasiquoter retains newlines in the string when the line is split across multiple lines. The unwords . lines idiom can be used on the resulting string to collapse it into a single line.

Setup

To execute the code examples provided in this module in ghci, please run the following commands first.

>>> :m
>>> :set -XQuasiQuotes
>>> import Streamly.Internal.Unicode.String

str :: QuasiQuoter

A QuasiQuoter that treats the input as a string literal:

>>> [str|x|]
"x"

Any #{symbol} is replaced by the value of the Haskell symbol symbol which is in scope:

>>> x = "hello"
>>> [str|#{x} world!|]
"hello world!"

## means a literal # without the special meaning for referencing haskell symbols:

>>> [str|##{x} world!|]
"#{x} world!"

A # at the end of line means the line continues to the next line without introducing a newline character:

>>> :{
[str|hello#
world!|]
:}
"hello world!"

Bugs: because of a bug in parsers, a lone # at the end of input gets removed.