character_classes

Mirrors graphql-js language/characterClasses.ts.

All predicates take a Unicode code point as an Int and return whether the code point participates in the named GraphQL lexical class. Inputs outside the BMP are accepted but only ASCII-range answers are meaningful; graphql-js itself only checks for ASCII letters/digits in these classes.

Values

is_digit

pub fn is_digit(code: Int) -> Bool

Digit :: 0..9

is_letter

pub fn is_letter(code: Int) -> Bool

Letter :: A..Z | a..z

is_name_continue

pub fn is_name_continue(code: Int) -> Bool

NameContinue :: Letter | Digit | "_"

is_name_start

pub fn is_name_start(code: Int) -> Bool

NameStart :: Letter | "_"

is_unicode_scalar_value

pub fn is_unicode_scalar_value(code: Int) -> Bool

Whether a code point is a valid Unicode scalar value (anything except surrogate code points). graphql-js isUnicodeScalarValue.

is_white_space

pub fn is_white_space(code: Int) -> Bool

WhiteSpace :: Horizontal Tab (U+0009) | Space (U+0020)

read_hex_digit

pub fn read_hex_digit(code: Int) -> Int

HexDigit :: 0..9 | A..F | a..f. Returns the integer value 0..15, or -1 when code is not a hex digit (matches graphql-js’s sentinel).