Returns the field value for a field name

Example:

data Project = Project { name :: Text, isPublic :: Bool }

let project = Project { name = "Hello World", isPublic = False }

>>> get #name project
"Hello World"

>>> get #isPublic project
False

Sets a field of a record and returns the new record.

Example:

data Project = Project { name :: Text, isPublic :: Bool }

let project = Project { name = "Hello World", isPublic = False }

>>> set #name "New Name" project
Project { name = "New Name", isPublic = False }

>>> set #isPublic True project
Project { name = "Hello World", isPublic = True }

Like set but wraps the value with a Just. Useful when you want to set a Maybe field

Example:

data Project = Project { name :: Maybe Text }

let project = Project { name = Nothing }

>>> setJust #name "New Name" project
Project { name = Just "New Name" }

Like set but doesn't set the value if it's Nothing. Useful when you update NULL values | e.g. via a cron job and don't want to lose that work on subsequent updates.

Example:

data Project = Project { name :: Maybe Text }

let project = Project { name = Nothing }

>>> setMaybe #name (Just "New Name") project
Project { name = Just "New Name" }

>>> setMaybe #name Nothing project
Project { name = Just "New Name" } -- previous value is kept

Plus 1 on record field.

Example:

data Project = Project { name :: Text, followersCount :: Int }

let project = Project { name = "Hello World", followersCount = 0 }

>>> project |> incrementField #followersCount
Project { name = "Hello World", followersCount = 1 }

Minus 1 on a record field.

Example:

data Project = Project { name :: Text, followersCount :: Int }

let project = Project { name = "Hello World", followersCount = 1337 }

>>> project |> decrementField #followersCount
Project { name = "Hello World", followersCount = 1336 }

Example:

forEach users \user -> putStrLn (tshow user)

Example: Within HSX

renderUser :: User -> Html
renderUser user = [hsx|<div>User: {get #name user}</div>|]

render = [hsx|{forEach users renderUser}|]

Like forEach but with an index, starting at 0

Example: With a Callback

forEachWithIndex users \(index, user) -> putStrLn (tshow index <> ": " <> tshow user)

Example: With a Function

printUser :: (Int, User) -> IO ()
printUser (index, user) = putStrLn (tshow index <> ": " <> tshow user)

forEachWithIndex users printUser

Example: Within HSX

renderUser :: (Int, User) -> Html
renderUser (index, user) = [hsx|<div>User {index}: {get #name user}</div>|]

render = [hsx|{forEachWithIndex users renderUser}|]

Parses a text to an int. Returns Nothing on failure.

Example:

>>> textToInt "1337"
Just 1337

>>> textToInt "bad input"
Nothing

Returns True when day is Saturday or Sunday.

Example:

>>> isWeekend $ fromGregorian 2019 10 7
False

>>> isWeekend $ fromGregorian 2020 6 13
True

Returns True when today is Saturday or Sunday.

Example:

do
    todayIsWeekend <- isWeekend
    when todayIsWeekend (putStrLn "It's weekend!")

Debug-print a value during evaluation

Alias for traceShowId

Removes all html tags from a given html text

>>> stripTags "This is <b>Bold</b>"
"This is Bold"

Returns the value of a type level symbol as a text

>>> symbolToText @"hello"
"hello"

>>> symbolToText @(GetTableName User)
"users"

Returns the value of a type level symbol as a bytestring

>>> symbolToByteString @"hello"
"hello"

>>> symbolToByteString @(GetTableName User)
"users"

Used by nonEmpty and isEmptyValue to check for emptyness

Provides the copyFields function

Useful to rewrite getter-setter code like this:

let newProject = newRecord @Project
    |> set #name (get #name otherProject)
    |> set #isPublic (get #isPublic otherProject)
    |> set #userId (get #userId otherProject)

With copyFields this can be written like this:

let newProject = newRecord @Project
    |> copyFields @["name", "isPublic", "userId"] otherProject

Returns a list of all values of an enum type

Given a data structure like this:

data Color = Yellow | Red | Blue deriving (Enum)

You can call allEnumValues to get a list of all colors:

>>> allEnumValues @Color
[Yellow, Red, Blue]

This also works if the enum is defined in the Schema.sql:

CREATE TYPE brokerage_subscription_type AS ENUM ('basic_subscription', 'bronze_subscription', 'silver_subscription', 'gold_subscription');

>>> allEnumValues @BrokerageSubscriptionType
[BasicSubscription, BronzeSubscription, SilverSubscription]