Text
Text values
This type represents human-readable text as sequences of characters of type [Char](Char.html) .
If t is a value of type Text, then:
* t.chars() returns an iterator of type Iter<Char> enumerating its characters from first to last.
* t.size() returns the size (or length) of t (and t.chars()) as a Nat.
This module defines additional operations on Text values.
fromChar
let fromChar : (c : Char) -> TextConversion.
Returns the text value of size 1 containing the single character c.
toIter
func toIter(t : Text) : Iter.Iter<Char>Conversion.
Creates an iterator that traverses the characters of the text t.
fromIter
func fromIter(cs : Iter.Iter<Char>) : TextConversion.
Returns the text value containing the sequence of characters in cs.
hash
func hash(t : Text) : Hash.HashReturns a hash obtained by using the djb2 algorithm from http://www.cse.yorku.ca/~oz/hash.html
This function is good enough for use in a hash-table but it’s not a cryptographic hash function!
compare
func compare(t1 : Text, t2 : Text) : {#less; #equal; #greater}Returns the order of t1 and t1.
join
func join(sep : Text, ts : Iter.Iter<Text>) : TextReturns the concatenation of text values in ts, separated by sep.
map
func map(t : Text, f : Char -> Char) : TextReturns the result of applying f to each character in ts, concatenating the intermediate single-character text values.
translate
func translate(t : Text, f : Char -> Text) : TextReturns the result of applying f to each character in ts, concatenating the intermediate text values.
Pattern
type Pattern = {#char : Char; #text : Text; #predicate : (Char -> Bool)}A pattern p describes a sequence of characters. A pattern has one of the following forms:
-
#char cmatches the single character sequence,c. -
#predicate pmatches any single character sequencecsatisfying predicatep(c). -
#text tmatches multi-character text sequencet.
A match for p is any sequence of characters matching the pattern p.
contains
func contains(t : Text, p : Pattern) : BoolReturns true if t contains a match for pattern p.
startsWith
func startsWith(t : Text, p : Pattern) : BoolReturns true if t starts with a prefix matching pattern p, otherwise returns false.
endsWith
func endsWith(t : Text, p : Pattern) : BoolReturns true if t ends with a suffix matching pattern p, otherwise returns false.
replace
func replace(t : Text, p : Pattern, r : Text) : TextReturns t with all matches of pattern p replaced by text r.
stripStart
func stripStart(t : Text, p : Pattern) : ?TextReturns the optioned suffix of t obtained by eliding exactly one leading match of pattern p, otherwise null.
stripEnd
func stripEnd(t : Text, p : Pattern) : ?TextReturns the optioned prefix of t obtained by eliding exactly one trailing match of pattern p, otherwise null.
trimStart
func trimStart(t : Text, p : Pattern) : TextReturns the suffix of t obtained by eliding all leading matches of pattern p.
trimEnd
func trimEnd(t : Text, p : Pattern) : TextReturns the prefix of t obtained by eliding all trailing matches of pattern p.
trim
func trim(t : Text, p : Pattern) : TextReturns the subtext of t obtained by eliding all leading and trailing matches of pattern p.