proc

When to use lambda, when to use Proc.new?

橙三吉。 提交于 2019-11-26 10:58:42
In Ruby 1.8, there are subtle differences between proc/lambda on the one hand, and Proc.new on the other. What are those differences? Can you give guidelines on how to decide which one to choose? In Ruby 1.9, proc and lambda are different. What's the deal? Joey deVilla Another important but subtle difference between procs created with lambda and procs created with Proc.new is how they handle the return statement: In a lambda -created proc, the return statement returns only from the proc itself In a Proc.new -created proc, the return statement is a little more surprising: it returns control not

how can i show the size of files in /proc? it should not be size zero

≯℡__Kan透↙ 提交于 2019-11-26 10:57:05
from the following message, we know that there are two characters in file /proc/sys/net/ipv4/ip_forward, but why ls just showed this file is of size zero? i know this is not a file on disk, but a file in the memory, so is there any command which i can see the real size of the files in /proc? root@OpenWrt:/proc/sys/net/ipv4# cat ip_forward | wc -c 2 root@OpenWrt:/proc/sys/net/ipv4# ls -l ip_forward -rw-r--r-- 1 root root 0 Sep 3 00:20 ip_forward root@OpenWrt:/proc/sys/net/ipv4# pwd /proc/sys/net/ipv4 Those are not really files on disk (as you mention) but they are also not files in memory - the

What does to_proc method mean?

纵然是瞬间 提交于 2019-11-26 10:22:10
问题 I am learning rails and following this thread. I am stuck with the to_proc method. I consider symbols only as alternatives to strings (they are like strings but cheaper in terms of memory). If there is anything else I am missing for symbols, then please tell me. Please explain in simple way what to_proc means and what it is used for. 回答1: Some methods take a block, and this pattern frequently appears for a block: {|x| x.foo} and people would like to write that in a more concise way. In order

how can i show the size of files in /proc? it should not be size zero

家住魔仙堡 提交于 2019-11-26 03:28:45
问题 from the following message, we know that there are two characters in file /proc/sys/net/ipv4/ip_forward, but why ls just showed this file is of size zero? i know this is not a file on disk, but a file in the memory, so is there any command which i can see the real size of the files in /proc? root@OpenWrt:/proc/sys/net/ipv4# cat ip_forward | wc -c 2 root@OpenWrt:/proc/sys/net/ipv4# ls -l ip_forward -rw-r--r-- 1 root root 0 Sep 3 00:20 ip_forward root@OpenWrt:/proc/sys/net/ipv4# pwd /proc/sys

When to use lambda, when to use Proc.new?

混江龙づ霸主 提交于 2019-11-26 02:15:33
问题 In Ruby 1.8, there are subtle differences between proc/lambda on the one hand, and Proc.new on the other. What are those differences? Can you give guidelines on how to decide which one to choose? In Ruby 1.9, proc and lambda are different. What\'s the deal? 回答1: Another important but subtle difference between procs created with lambda and procs created with Proc.new is how they handle the return statement: In a lambda -created proc, the return statement returns only from the proc itself In a