Ruby StringScanner peep函数

StringScanner#peep() : peep()是StringScanner类的一个方法，它返回一个对应于string[pos, len]的字符串。

语法。StringScanner.peep()

参数。StringScanner值

len – 字符串值的长度

返回：对应于string[pos, len]的字符串。

例子 #1 :

# Ruby code for StringScanner.peep() method
  
# loading StringScanner
require 'strscan'
  
# declaring StringScanner 
c = StringScanner.new("Mon Sep 12 2018 14:39")
  
# peep() method
puts "String Scanner peep form : #{c.peep(3)}\n\n"
  
# peep() method
puts "String Scanner peep form : #{c.peep(6)}\n\n"
  
# peep() method
puts "String Scanner peep form : #{c.peep(9)}\n\n"

输出:

String Scanner peep form : Mon

String Scanner peep form : Mon Se

String Scanner peep form : Mon Sep 1

例子 #2 :

# Ruby code for StringScanner.peep() method
  
# loading StringScanner
require 'strscan'
  
# declaring StringScanner 
c = StringScanner.new("hellogeeks")
  
# peep() method
puts "String Scanner peep form : #{c.peep(2)}\n\n"
  
# peep() method
puts "String Scanner peep form : #{c.peep(4)}\n\n"
  
# peep() method
puts "String Scanner peep form : #{c.peep(8)}\n\n"

输出:

String Scanner peep form : he

String Scanner peep form : hell

String Scanner peep form : hellogee