Data.String.NonEmpty.Internal

newtype NonEmptyString

A string that is known not to be empty.

You can use this constructor to create a NonEmptyString that isn't non-empty, breaking the guarantee behind this newtype. It is provided as an escape hatch mainly for the Data.NonEmpty.CodeUnits and Data.NonEmpty.CodePoints modules. Use this at your own risk when you know what you are doing.

Constructors

• NonEmptyString String

Instances

• Eq NonEmptyString
• Ord NonEmptyString
• Semigroup NonEmptyString
• Show NonEmptyString

class MakeNonEmpty :: Symbol -> Constraintclass MakeNonEmpty (s :: Symbol)  where

A helper class for defining non-empty string values at compile time.

something :: NonEmptyString
something = nes (Proxy :: Proxy "something")

Members

• nes :: Proxy s -> NonEmptyString

Instances

• (Fail (Text "Cannot create an NonEmptyString from an empty Symbol")) => MakeNonEmpty ""
• (IsSymbol s) => MakeNonEmpty s

newtype NonEmptyReplacement

A newtype used in cases to specify a non-empty replacement for a pattern.

Constructors

• NonEmptyReplacement NonEmptyString

Instances

• Eq NonEmptyReplacement
• Ord NonEmptyReplacement
• Semigroup NonEmptyReplacement
• Show NonEmptyReplacement

fromString :: String -> Maybe NonEmptyString

Creates a NonEmptyString from a String, returning Nothing if the input is empty.

fromString "" = Nothing
fromString "hello" = Just (NES.unsafeFromString "hello")

unsafeFromString :: Partial => String -> NonEmptyString

A partial version of fromString.

toString :: NonEmptyString -> String

Converts a NonEmptyString back into a standard String.

appendString :: NonEmptyString -> String -> NonEmptyString

Appends a string to this non-empty string. Since one of the strings is non-empty we know the result will be too.

appendString (NonEmptyString "Hello") " world" == NonEmptyString "Hello world"
appendString (NonEmptyString "Hello") "" == NonEmptyString "Hello"

prependString :: String -> NonEmptyString -> NonEmptyString

Prepends a string to this non-empty string. Since one of the strings is non-empty we know the result will be too.

prependString "be" (NonEmptyString "fore") == NonEmptyString "before"
prependString "" (NonEmptyString "fore") == NonEmptyString "fore"

stripPrefix :: Pattern -> NonEmptyString -> Maybe NonEmptyString

If the string starts with the given prefix, return the portion of the string left after removing it. If the prefix does not match or there is no remainder, the result will be Nothing.

stripPrefix (Pattern "http:") (NonEmptyString "http://purescript.org") == Just (NonEmptyString "//purescript.org")
stripPrefix (Pattern "http:") (NonEmptyString "https://purescript.org") == Nothing
stripPrefix (Pattern "Hello!") (NonEmptyString "Hello!") == Nothing

stripSuffix :: Pattern -> NonEmptyString -> Maybe NonEmptyString

If the string ends with the given suffix, return the portion of the string left after removing it. If the suffix does not match or there is no remainder, the result will be Nothing.

stripSuffix (Pattern ".exe") (NonEmptyString "purs.exe") == Just (NonEmptyString "purs")
stripSuffix (Pattern ".exe") (NonEmptyString "purs") == Nothing
stripSuffix (Pattern "Hello!") (NonEmptyString "Hello!") == Nothing

contains :: Pattern -> NonEmptyString -> Boolean

Checks whether the pattern appears in the given string.

contains (Pattern "needle") (NonEmptyString "haystack with needle") == true
contains (Pattern "needle") (NonEmptyString "haystack") == false

localeCompare :: NonEmptyString -> NonEmptyString -> Ordering

Compare two strings in a locale-aware fashion. This is in contrast to the Ord instance on String which treats strings as arrays of code units:

NonEmptyString "ä" `localeCompare` NonEmptyString "b" == LT
NonEmptyString "ä" `compare` NonEmptyString "b" == GT

replace :: Pattern -> NonEmptyReplacement -> NonEmptyString -> NonEmptyString

Replaces the first occurence of the pattern with the replacement string.

replace (Pattern "<=") (NonEmptyReplacement "≤") (NonEmptyString "a <= b <= c") == NonEmptyString "a ≤ b <= c"

replaceAll :: Pattern -> NonEmptyReplacement -> NonEmptyString -> NonEmptyString

Replaces all occurences of the pattern with the replacement string.

replaceAll (Pattern "<=") (NonEmptyReplacement "≤") (NonEmptyString "a <= b <= c") == NonEmptyString "a ≤ b ≤ c"

toLower :: NonEmptyString -> NonEmptyString

Returns the argument converted to lowercase.

toLower (NonEmptyString "hElLo") == NonEmptyString "hello"

toUpper :: NonEmptyString -> NonEmptyString

Returns the argument converted to uppercase.

toUpper (NonEmptyString "Hello") == NonEmptyString "HELLO"

trim :: NonEmptyString -> Maybe NonEmptyString

Removes whitespace from the beginning and end of a string, including whitespace characters and line terminators. If the string is entirely made up of whitespace the result will be Nothing.

trim (NonEmptyString "   Hello  \n World\n\t    ") == Just (NonEmptyString "Hello  \n World")
trim (NonEmptyString "   \n") == Nothing

joinWith :: forall f. Foldable f => String -> f NonEmptyString -> String

Joins the strings in a container together as a new string, inserting the first argument as separator between them. The result is not guaranteed to be non-empty.

joinWith ", " [NonEmptyString "apple", NonEmptyString "banana"] == "apple, banana"
joinWith ", " [] == ""

join1With :: forall f. Foldable1 f => String -> f NonEmptyString -> NonEmptyString

Joins non-empty strings in a non-empty container together as a new non-empty string, inserting a possibly empty string as separator between them. The result is guaranteed to be non-empty.

-- array syntax is used for demonstration here, it would need to be a real `Foldable1`
join1With ", " [NonEmptyString "apple", NonEmptyString "banana"] == NonEmptyString "apple, banana"
join1With "" [NonEmptyString "apple", NonEmptyString "banana"] == NonEmptyString "applebanana"

joinWith1 :: forall f. Foldable1 f => NonEmptyString -> f String -> NonEmptyString

Joins possibly empty strings in a non-empty container together as a new non-empty string, inserting a non-empty string as a separator between them. The result is guaranteed to be non-empty.

-- array syntax is used for demonstration here, it would need to be a real `Foldable1`
joinWith1 (NonEmptyString ", ") ["apple", "banana"] == NonEmptyString "apple, banana"
joinWith1 (NonEmptyString "/") ["a", "b", "", "c", ""] == NonEmptyString "a/b//c/"

liftS :: forall r. (String -> r) -> NonEmptyString -> r