有什么办法能让这看起来好一点吗?

conn.exec 'select attr1, attr2, attr3, attr4, attr5, attr6, attr7 ' +
          'from table1, table2, table3, etc, etc, etc, etc, etc, ' +
          'where etc etc etc etc etc etc etc etc etc etc etc etc etc'

比如,有没有办法暗示串联?


当前回答

其他选项:

#multi line string
multiline_string = <<EOM
This is a very long string
that contains interpolation
like #{4 + 5} \n\n
EOM

puts multiline_string

#another option for multiline string
message = <<-EOF
asdfasdfsador #{2+2} this month.
asdfadsfasdfadsfad.
EOF

puts message

其他回答

今天的优雅回答:

<<~TEXT
Hi #{user.name}, 

Thanks for raising the flag, we're always happy to help you.
Your issue will be resolved within 2 hours.
Please be patient!

Thanks again,
Team #{user.organization.name}
TEXT

<<-TEXT和<<~TEXT有区别,前者保留了块内的空格,后者则没有。

还有其他的选择。 比如串联等等,但这个更有意义。

如果我错了,请告诉我…

最近,随着Ruby 2.3的新特性,新的弯弯曲曲的HEREDOC将允许您以一种非常好的方式编写多行字符串,并且只需要进行最小的更改,因此,将它与.squish(如果您正在使用rails)结合使用将使您以一种非常好的方式编写多行字符串! 在只使用ruby的情况下,您可以执行<<~SQL.split。Join(" "),几乎相同

[1] pry(main)> <<~SQL.squish
[1] pry(main)*   select attr1, attr2, attr3, attr4, attr5, attr6, attr7
[1] pry(main)*   from table1, table2, table3, etc, etc, etc, etc, etc,
[1] pry(main)*   where etc etc etc etc etc etc etc etc etc etc etc etc etc
[1] pry(main)* SQL
=> "select attr1, attr2, attr3, attr4, attr5, attr6, attr7 from table1, table2, table3, etc, etc, etc, etc, etc, where etc etc etc etc etc etc etc etc etc etc etc etc etc"

裁判:https://infinum.co/the-capsized-eight/multiline-strings-ruby-2-3-0-the-squiggly-heredoc

是的,如果你不介意额外的换行被插入:

 conn.exec 'select attr1, attr2, attr3, attr4, attr5, attr6, attr7
            from table1, table2, table3, etc, etc, etc, etc, etc,
            where etc etc etc etc etc etc etc etc etc etc etc etc etc'

你也可以使用heredoc:

conn.exec <<-eos
   select attr1, attr2, attr3, attr4, attr5, attr6, attr7
   from table1, table2, table3, etc, etc, etc, etc, etc,
   where etc etc etc etc etc etc etc etc etc etc etc etc etc
eos
conn.exec = <<eos
  select attr1, attr2, attr3, attr4, attr5, attr6, attr7
  from table1, table2, table3, etc, etc, etc, etc, etc,
  where etc etc etc etc etc etc etc etc etc etc etc etc etc
eos

有时值得删除新的行字符\n,如:

conn.exec <<-eos.squish
 select attr1, attr2, attr3, attr4, attr5, attr6, attr7
 from table1, table2, table3, etc, etc, etc, etc, etc,
 where etc etc etc etc etc etc etc etc etc etc etc etc etc
eos