Char and String Types

Char

The Char type is written in single quotes. We can also use Unicode code points in hexadecimal to create a char. Note the \x… escape sequence.

charZ :: Char
charZ = 'Z'

check :: Char
check = '\x2714'
-- → ✔

String

The String type is written with double quotes.

Unlike in some other languages, line continuation requires not one escape, but two.

hello :: String
hello = "Hello, world!"

withNl :: String
withNl = "Contains a\nnewline."

Multi-line:

multi :: String
multi = "This string\
        \ spawns over\
        \ multiple lines, but spaces\
        \ to the \
        \ left of the ‘\\’ are ignored.\
        \\n\
        \ Oh, and Unicode code points\
        \ work too \x2714! 💖"

> log multi
This string spawns over multiple lines, but spaces to the left of the ‘\’ are ignored.
 Oh, and Unicode code points work too ✔! 💖

Spaces before the trailing \ concatenate with spaces after the leading \.

Unicode

We can use \x escapes with hexadecimal numbers to denote a Unicode code point.

Char

For Char, as of PureScript 0.15, it seems we can use up to 4 bytes:

> '\x2714'
'✔'

> '\x2717'
'✗'

> '\x03bb'
'λ'

> '\x203d'
'‽'

> '\x0001f4a9'
Unexpected a at line 1, column 10
> '\x1f4a9'
Illegal astral code point in character literal at line 1, column 9

String

For String, we can use up to 6 bytes (which as of 2022, is enough every Unicode code point without using surrogates, since as of this day, Unicode goes up to 10FFFF).

> "\x2714"
"✔"

> "\x1f4a9"
"💩"

> "\x01f4a9"
"💩"

> "\x0001f4a9"
"💩"

Surrogates work with String, but not with Char:

> "\xD83d\xDCA9"
"💩"

> '\xD83d\xDCA9'
Unexpected \ at line 1, column 8

See this discussion on the PureScript Discord server about this topic and this issue on the PureScript repo.