Text.Builder

Text assembled by appending.

A builder is immutable: appending returns a new builder and leaves the old one answering exactly the text it had, whichever builders extend it, in whatever order, and from whichever tasks. Appending in sequence costs amortized time proportional to the text appended.

Append operations take the text or scalar first and the builder last, so they compose with |>.

import Text.Builder

built = Text.Builder.empty |> Text.Builder.append "foo" |> Text.Builder.appendInt 123
Text.Builder.toString built == "foo123"

Builder

type BuilderSource

Text built by appending. Builders have no equality or display; compare or show their toString.

append

append : String -> Builder -> BuilderSource

The builder with text appended. Extending the most recently extended builder reuses available storage; extending an older one copies its text.

import Text.Builder

base = Text.Builder.append "a" Text.Builder.empty
left = Text.Builder.append "b" base
right = Text.Builder.append "c" base

Text.Builder.toString left == "ab"
Text.Builder.toString right == "ac"
Text.Builder.toString base == "a"

appendChar

appendChar : Char -> Builder -> BuilderSource

The builder with one character appended.

import Text.Builder

Text.Builder.toString (Text.Builder.appendChar 'k' (Text.Builder.append "o" Text.Builder.empty)) == "ok"

appendCharLiteral

appendCharLiteral : Char -> Builder -> BuilderSource

Appends the quoted, escaped source representation of a Char, without an intermediate string. Its spelling agrees with show.

appendFloat

appendFloat : Float -> Builder -> BuilderSource

The builder with a float’s display appended without an intermediate string. Its spelling is the same as show: shortest round-trip decimals, unpadded exponents outside the ordinary decimal range, Infinity, and NaN.

import Text.Builder

Text.Builder.toString (Text.Builder.appendFloat 1.25 Text.Builder.empty) == "1.25"

appendInt

appendInt : Int -> Builder -> BuilderSource

The builder with an integer’s decimal display appended without an intermediate string.

import Text.Builder

Text.Builder.toString (Text.Builder.appendInt (-42) Text.Builder.empty) == "-42"

appendStringLiteral

appendStringLiteral : String -> Builder -> BuilderSource

Appends the quoted, escaped source representation of a String, without an intermediate string. Its spelling agrees with show.

charLiteral

charLiteral : Char -> StringSource

The quoted, escaped source representation of a character.

charToString

charToString : Char -> StringSource

A string containing one character, without quoting or escaping.

empty

empty : BuilderSource

The builder holding no text.

floatToString

floatToString : Float -> StringSource

The float representation used by appendFloat, without allocating a builder.

intToString

intToString : Int -> StringSource

The decimal representation of an integer, without allocating a builder.

isEmpty

isEmpty : Builder -> BoolSource

Whether the builder holds no text.

import Text.Builder

Text.Builder.isEmpty Text.Builder.empty
Text.Builder.isEmpty (Text.Builder.append "" Text.Builder.empty)

stringLiteral

stringLiteral : String -> StringSource

The quoted, escaped source representation of a string, including escaping #{.

toString

toString : Builder -> StringSource

The text the builder holds, copied once.