% cabal build
Building yesod-markdown-0.8.4...
Preprocessing library yesod-markdown-0.8.4...
[1 of 1] Compiling Yesod.Markdown ( Yesod/Markdown.hs, dist/build/Yesod/Markdown.o )
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package array-0.5.0.0 ... linking ... done.
Loading package deepseq-1.3.0.2 ... linking ... done.
Loading package bytestring-0.10.4.0 ... linking ... done.
Loading package containers-0.5.5.1 ... linking ... done.
Loading package text-1.1.0.1 ... linking ... done.
Loading package hashable-1.2.1.0 ... linking ... done.
Loading package scientific-0.2.0.2 ... linking ... done.
Loading package attoparsec-0.11.2.1 ... linking ... done.
Loading package dlist-0.7.0.1 ... linking ... done.
Loading package transformers-0.3.0.0 ... linking ... done.
Loading package mtl-2.1.3.1 ... linking ... done.
Loading package old-locale-1.0.0.6 ... linking ... done.
Loading package syb-0.4.1 ... linking ... done.
Loading package pretty-1.1.1.1 ... linking ... done.
Loading package template-haskell ... linking ... done.
Loading package time-1.4.2 ... linking ... done.
Loading package unordered-containers-0.2.4.0 ... linking ... done.
Loading package primitive-0.5.2.1 ... linking ... done.
Loading package vector-0.10.9.1 ... linking ... done.
Loading package aeson-0.7.0.3 ... linking ... done.
Loading package blaze-builder-0.3.3.2 ... linking ... done.
Loading package blaze-markup-0.6.0.0 ... linking ... done.
Loading package blaze-html-0.7.0.1 ... linking ... done.
Loading package byteable-0.1.1 ... linking ... done.
Loading package data-default-class-0.0.1 ... linking ... done.
Loading package data-default-instances-base-0.0.1 ... linking ... done.
Loading package data-default-instances-containers-0.0.1 ... linking ... done.
Loading package data-default-instances-dlist-0.0.1 ... linking ... done.
Loading package data-default-instances-old-locale-0.0.1 ... linking ... done.
Loading package data-default-0.5.3 ... linking ... done.
Loading package email-validate-2.0.1 ... linking ... done.
Loading package failure-0.2.0.2 ... linking ... done.
Loading package parsec-3.1.5 ... linking ... done.
Loading package filepath-1.3.0.2 ... linking ... done.
Loading package unix-2.7.0.1 ... linking ... done.
Loading package directory-1.2.1.0 ... linking ... done.
Loading package process-1.2.0.0 ... linking ... done.
Loading package system-filepath-0.4.10 ... linking ... done.
Loading package system-fileio-0.3.12 ... linking ... done.
Loading package shakespeare-1.2.1.1 ... linking ... done.
Loading package hamlet-1.1.9.2 ... linking ... done.
Loading package network-2.4.2.2 ... linking ... done.
Loading package base64-bytestring-1.0.0.1 ... linking ... done.
Loading package exceptions-0.5 ... linking ... done.
Loading package base-unicode-symbols-0.2.2.4 ... linking ... done.
Loading package transformers-base-0.4.1 ... linking ... done.
Loading package monad-control-0.3.2.3 ... linking ... done.
Loading package lifted-base-0.2.2.1 ... linking ... done.
Loading package mmorph-1.0.2 ... linking ... done.
Loading package resourcet-1.1.1 ... linking ... done.
Loading package text-stream-decode-0.1.0.5 ... linking ... done.
Loading package nats-0.1.2 ... linking ... done.
Loading package semigroups-0.13.0.1 ... linking ... done.
Loading package void-0.6.1 ... linking ... done.
Loading package conduit-1.1.0 ... linking ... done.
Loading package zlib-0.5.4.1 ... linking ... done.
Loading package streaming-commons-0.1.1 ... linking ... done.
Loading package conduit-extra-1.1.0 ... linking ... done.
Loading package fast-logger-2.1.5 ... linking ... done.
Loading package monad-loops-0.4.2 ... linking ... done.
Loading package stm-2.4.3 ... linking ... done.
Loading package stm-chans-3.0.0.2 ... linking ... done.
Loading package monad-logger-0.3.6 ... linking ... done.
Loading package path-pieces-0.1.3.1 ... linking ... done.
Loading package resource-pool-0.2.1.1 ... linking ... done.
Loading package silently-1.2.4.1 ... linking ... done.
Loading package persistent-1.3.0.6 ... linking ... done.
Loading package shakespeare-css-1.0.7.4 ... linking ... done.
Loading package shakespeare-js-1.2.0.4 ... linking ... done.
Loading package case-insensitive-1.2.0.0 ... linking ... done.
Loading package http-types-0.8.4 ... linking ... done.
Loading package vault-0.3.0.3 ... linking ... done.
Loading package wai-2.1.0.2 ... linking ... done.
Loading package css-text-0.1.2.1 ... linking ... done.
Loading package tagsoup-0.13.1 ... linking ... done.
Loading package utf8-string-0.3.7 ... linking ... done.
Loading package xss-sanitize-0.3.5.2 ... linking ... done.
Loading package attoparsec-conduit-1.1.0 ... linking ... done.
Loading package cereal-0.4.0.1 ... linking ... done.
Loading package securemem-0.1.3 ... linking ... done.
Loading package crypto-cipher-types-0.0.9 ... linking ... done.
Loading package cipher-aes-0.2.7 ... linking ... done.
Loading package crypto-random-0.0.7 ... linking ... done.
Loading package random-1.0.1.1 ... linking ... done.
Loading package cprng-aes-0.5.2 ... linking ... done.
Loading package entropy-0.2.2.4 ... linking ... done.
Loading package tagged-0.7.1 ... linking ... done.
Loading package crypto-api-0.13 ... linking ... done.
Loading package skein-1.0.9 ... linking ... done.
Loading package clientsession-0.9.0.3 ... linking ... done.
Loading package cookie-0.4.0.1 ... linking ... done.
Loading package safe-0.3.4 ... linking ... done.
Loading package shakespeare-i18n-1.0.0.5 ... linking ... done.
Loading package unix-compat-0.4.1.1 ... linking ... done.
Loading package ansi-terminal-0.6.1.1 ... linking ... done.
Loading package blaze-builder-conduit-1.1.0 ... linking ... done.
Loading package stringsearch-0.3.6.5 ... linking ... done.
Loading package byteorder-1.0.4 ... linking ... done.
Loading package old-time-1.1.0.2 ... linking ... done.
Loading package unix-time-0.2.2 ... linking ... done.
Loading package wai-logger-2.1.1 ... linking ... done.
Loading package word8-0.0.4 ... linking ... done.
Loading package zlib-conduit-1.1.0 ... linking ... done.
Loading package wai-extra-2.1.1.1 ... linking ... done.
Loading package http-date-0.0.4 ... linking ... done.
Loading package network-conduit-1.1.0 ... linking ... done.
Loading package simple-sendfile-0.2.13 ... linking ... done.
Loading package warp-2.1.4 ... linking ... done.
Loading package yesod-routes-1.2.0.6 ... linking ... done.
Loading package yesod-core-1.2.12 ... linking ... done.
Loading package persistent-template-1.3.1.3 ... linking ... done.
Loading package yesod-persistent-1.2.2.3 ... linking ... done.
Loading package yesod-form-1.3.8.2 ... linking ... done.
Loading package HTTP-4000.2.12 ... linking ... done.
Loading package binary-0.7.1.0 ... linking ... done.
Loading package extensible-exceptions-0.1.1.4 ... linking ... done.
Loading package regex-base-0.93.2 ... linking ... done.
Loading package regex-pcre-builtin-0.94.4.8.8.34 ... linking ... done.
Loading package highlighting-kate-0.5.6.1 ... linking ... done.
Loading package hslua-0.3.10 ... linking ... done.
Loading package pandoc-types-1.12.3.2 ... linking ... done.
Loading package temporary-1.2.0.2 ... linking ... done.
Loading package xml-1.3.13 ... linking ... done.
Loading package texmath-0.6.6.1 ... linking ... done.
Loading package yaml-0.8.8.1 ... linking ... done.
Loading package digest-0.0.1.2 ... linking ... done.
Loading package zip-archive-0.2.2 ... linking ... done.
Loading package pandoc-1.12.3.3 ... linking ... done.
Yesod/Markdown.hs:59:50:
Could not coerce from ‘m Text’ to ‘m Markdown’
because ‘m Text’ and ‘m Markdown’ are different types.
arising from the coercion of the method
‘persistent-1.3.0.6:Database.Persist.Sql.Class.sqlType’ from type
‘forall (m :: * -> *).
Monad m =>
m Text -> persistent-1.3.0.6:Database.Persist.Types.Base.SqlType’
to type
‘forall (m :: * -> *).
Monad m =>
m Markdown
-> persistent-1.3.0.6:Database.Persist.Types.Base.SqlType’
Possible fix:
use a standalone 'deriving instance' declaration,
so you can specify the instance context yourself
When deriving the instance for (PersistFieldSql Markdown)