PostgreSQL“找不到模块”

Question

我正在尝试将 Posgres 和cabal沙箱用于新项目。 我已经安装了postgresql-simple ，安装输出证明了这一点：

$ cabal install postgresql-simple
Resolving dependencies...
All the requested packages are already installed:
postgresql-simple-0.4.10.0
Use --reinstall if you want to reinstall anyway.
Notice: installing into a sandbox located at
/Users/inaimathi/projects/hs-test/.cabal-sandbox

但是当我尝试在ghci导入库时，出现错误

ghci
GHCi, version 7.10.1: http://www.haskell.org/ghc/  :? for help
Prelude> import Database.PostgreSQL.Simple
import Database.PostgreSQL.Simple

<no location info>:
    Could not find module ‘Database.PostgreSQL.Simple’
    It is not a module in the current program, or in any known package.
Prelude> 

谁能指出我做错了什么？

Answer 1

您需要使用指向/Users/inaimathi/projects/hs-test/.cabal-sandbox -package-db=...标志启动 GHCi

所以ghci -package-db=/Users/inaimathi/projects/hs-test/.cabal-sandbox或ghci -package-db=/Users/inaimathi/projects/hs-test/.cabal-sandbox ...