生成基於模式匹配

Question

從數組元素的字符串我有一個這樣的陣列：

inList = ["edge_rabbit", "nsp_edge_rabbit", "services", "syslog", "master_rabbit", "mongod", ...] 

如何可以採取與_rabbit或元件與格式mongo[cds]結束的元件，並且生成一個逗號分隔的字符串如下所示？

"edge_rabbit, nsp_edge_rabbit, master_rabbit" 

Answer 1

這是你正在尋找使用String#end_with?和Array#select的人嗎？

inList = ["edge_rabbit", "nsp_edge_rabbit", "services", "syslog", "master_rabbit", "mongod"] 
inList.select{|e| e.end_with?('_rabbit')}.join(", ") 
# => "edge_rabbit, nsp_edge_rabbit, master_rabbit" 

或

inList = ["edge_rabbit", "nsp_edge_rabbit", "services", "syslog", "master_rabbit", "mongod"] 
inList.grep(/_rabbit$/).join(", ") 
# => "edge_rabbit, nsp_edge_rabbit, master_rabbit" 


inList = ["edge_rabbit","_rabbit_ut", "nsp_edge_rabbit", "services", "syslog", "master_rabbit", "mongod","mongos","mongoy"] 
inList.grep(/_rabbit$|^mongo[cds]/).join(", ") 
# => "edge_rabbit, nsp_edge_rabbit, master_rabbit, mongod, mongos" 

Answer 2

我會使用一些小的模式：在mongo

in_list.grep(/(?:^mongo)|(?:_rabbit$)/).join(', ') # => "edge_rabbit, nsp_edge_rabbit, master_rabbit, mongod" 

如果有可能有變化與其他尾隨：

in_list = ["edge_rabbit", "nsp_edge_rabbit", "services", "syslog", "master_rabbit", "mongod"] 

in_list.select{ |s| s[/(?:^mongo)|(?:_rabbit$)/] }.join(', ') # => "edge_rabbit, nsp_edge_rabbit, master_rabbit, mongod" 

或者字符besid ES c，d或s，然後使用：

in_list.grep(/(?:^mongo[cds])|(?:_rabbit$)/).join(', ') # => "edge_rabbit, nsp_edge_rabbit, master_rabbit, mongod"