显示，隐藏 隐藏文件
shift + command + .
查看 brew 启动服务
brew services list
可以根据
brew services
提供的命令修改
命令就是 Spotlight 功能的终端界面
mdfind
截图文件格式
defaults write com.apple.screencapture type jpg
How to Avoid Floating Point Math Error in PHP and Python
php -r "var_dump(intval(0.58 * 100));”
int(57)
python3
>>>print(0.58*100)57.99999999999999
other languages http://0.30000000000000004.com
how did this happen http://www.laruence.com/2013/03/26/2884.html
Mathematical extensions in php and decimal module in python to avoid this
php -r "var_dump(intval(bcmul('0.58', '100')));"
int(58)
>>> from decimal import Decimal
>>> from decimal import getcontext
>>> print(Decimal('0.58') * Decimal('100'))
58.00
MySQL 查询表字段
查询数据库中某个字段的使用情况，可以借助 MySQL 的 information_schema
例：查询 user_name 的字段
SELECT * FROM `information_schema`.`columns` WHERE `column_name` = 'user_name';
亦支持 like
SELECT * FROM `information_schema`.`columns` WHERE `column_name` LIKE '%user_name%';
CodeRunner Go
- Go to the settings panel (preferences) of CodeRunner
- Choose the
Languagespanel and search “Go” - on the “Go” item, uncheck “Language uses compile script”
- replace the existing “Run command” by
go run $filename