Ruby11 拾遗

摘要

whileuntilloopbreaknext=~ 正则匹配 匹配到返回首字符匹配的位置，匹配不到返回nil

Agenda

1. Loop
2. Expression
3. File Read/Write
4. Debug
5. Process & Thread

Loop

while

a = 10 while a > 0   puts a   a -= 1 end

until

a = 100  until a == 0   puts a   a -= 1 end

loop

a = 10  loop do   break if a <= 0   puts a   a -= 1 end

循环控制

1. break
2. next

break

for x in 1..10   break if x == 5   puts x end

next

for x in 1..10   next if x == 6   puts x end

Expression

=~ 正则匹配 匹配到返回首字符匹配的位置，匹配不到返回nil

/hello/i =~ "hello world" # => 0

!~ 正则匹配 是否匹配不到 匹配到返回fals 匹配不到返回true

/666/i !~ "hello world" # => true

alias 别名

def hello   'hello' end  alias old_hello hello  def hello   'new hello' end  puts old_hello puts hello

File Read/Write 文件读写

1. File.read
2. File.readlines
3. File#rewind etc
4. IO.read/write

File Read

file = File.open('run.log', 'r') while line = file.gets   puts line end

File Write

file = File.open('run.log', 'a+') file.puts 'hello' file.close

File.open('run.log', 'a+') do |f|   f.puts 'hello' end

Debug

Debug 工具

1. ruby debugger
2. byebug

byebug

$ gem install byebug

require 'byebug'  def hello name   byebug #此处会有断电，然后可以看上下文的变量   puts name end  hello 'world'

Process & Thread 进程和线程

Process

pid = Process.fork{   #... }

Thread

Thread.new{   #... }