esqueleto-compat: Compatibility operators for Persistent and Esqueleto

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Dependencies base (>=4.13 && <5), conduit, esqueleto, persistent, resourcet, transformers [details]
License BSD-3-Clause
Copyright 2023 Matt von Hagen
Author Matt von Hagen
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Source repo head: git clone
Uploaded by parsonsmatt at 2023-10-20T16:22:39Z
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Last success reported on 2023-10-20 [all 1 reports]

Readme for esqueleto-compat-

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This library aims to provide compatibility operators that can allow esqueleto and persistent to be imported together.

Operators like ==. and >=. are defined as class members, and you can use them in the same module. Functions like update that are shared in both libraries are given an E suffix for the esqueleto version. And functions for operating on SqlExpr are given an _ suffix when the name would otherwise be a conflict.


import Database.Esqueleto.Compat

foo :: MonadIO m => TableId -> SqlPersistT m ()
foo tableKey = do
    -- Esqueleto:
    updateE $ \table -> do
        set [table ^. TableField =. val "Hello"] table
        where_ $ table ^. TableId ==. val tableKey

    -- Persistent
    update tableKey [TableField =. "Goodbye"]

    -- Esqueleto:
    select $ do
        pure $ exists_ $ do
            t <- from $ table @Table
            where_ $ t ^. TableField ==. val "Hello"

    -- Persistent
    exists [TableField ==. val "Hello"]