语言扩展名#!/bin/sh
while read oldrev newrev ref
do
# only checking out the master (or whatever branch you would like to deploy)
if [[ $ref = refs/heads/master ]];
then
echo "Master ref received. Deploying master branch to production..."
git --work-tree=/home/mywebsite/public_html --git-
dir=/home/mywebsite/gitrepo/mywebsite.git checkout -f master
else
if [[ $ref = refs/heads/dev ]];
then
echo "Development ref received. Deploying dev branch to staging..."
git --work-tree=/home/mywebsite/dev_public_html --git-dir=/home/mywebsite/gitrepo/mywebsite.git checkout -f dev
else
echo "Ref $ref successfully received. Doing nothing: only the master branch may be deployed on this server."
fi
fi
done
使得可以但不必将类型变量与ExplicitForall绑定。
例如，以下程序会编译
forall但是，下面的程序也没有编译{-# LANGUAGE ExplicitForAll #-}
-- cps1.hs
-- non-cps definition of add
add :: Int -> Int -> Int
add x y = x + y
-- cps definition of add
add_cps :: forall r . Int -> Int -> (Int -> r) -> r
add_cps x y k = k (add x y)
的明确量词。
r是否存在某种语言扩展或编译器标志的组合，它们会使第二个程序无法编译？
答案 0 :(得分：2)
不，GHC当前没有工具。