Definitions for String

This file defines a bunch of functions for the String datatype.

def String.leftpad (n : Nat) (c : optParam Char ' ') (s : String) : String

Pad s : String with repeated occurrences of c : Char until it's of length n. If s is initially larger than n, just return s.

Equations

• String.leftpad n c s = { data := List.leftpad n c s.data }

def String.replicate (n : Nat) (c : Char) : String

Construct the string consisting of n copies of the character c.

Equations

• String.replicate n c = { data := List.replicate n c }

def String.rightpad (n : Nat) (c : optParam Char ' ') (s : String) : String

Pad s : String with repeated occurrences of c : Char on the right until it's of length n. If s is initially larger than n, just return s.

Equations

• String.rightpad n c s = s ++ String.replicate (n - s.length) c

def String.IsPrefix : String → String → Prop

s.IsPrefix t checks if the string s is a prefix of the string t.

Equations

• x✝.IsPrefix x = match x✝, x with | { data := d1 }, { data := d2 } => d1 <+: d2

def String.IsSuffix : String → String → Prop

s.IsSuffix t checks if the string s is a suffix of the string t.

Equations

• x✝.IsSuffix x = match x✝, x with | { data := d1 }, { data := d2 } => d1 <:+ d2

def String.mapTokens (c : Char) (f : String → String) : String → String

String.mapTokens c f s tokenizes s : string on c : char, maps f over each token, and then reassembles the string by intercalating the separator token c over the mapped tokens.

Equations

• String.mapTokens c f = (String.singleton c).intercalate ∘ List.map f ∘ fun (x : String) => x.split fun (x : Char) => decide (x = c)

def String.getRest (s : String) (t : String) : Option String

getRest s t returns some r if s = t ++ r. If t is not a prefix of s, it returns none.

Equations

• s.getRest t = List.asString <$> s.toList.getRest t.toList

def String.head (s : String) : Char

Produce the head character from the string s, if s is not empty, otherwise 'A'.

Equations

• s.head = s.iter.curr