首页 > 代码库 > LRTHW练习八
LRTHW练习八
正确代码：
formatter = "% {first} % {second} % {third} % {fourth}"puts formatter % {first: 1, second: 2,third: 3,fourth: 4}puts formatter % {first: "one", second: "two", third: "three", fourth: "four"}puts formatter % {first: true, second: false, third: true, fourth: false}puts formatter % {first: formatter,second: formatter, third: formatter, fourth: formatter}puts formatter % { first: "I had this things" , second: "That you could type uo right.", third: "But it didn‘t sing ." , fourth: "So I said goodnight."}
显示正确的结果：
[ufindme@ufindme rubywork]$ ruby ex8.rb 1 2 3 4one two three fourtrue false true false% {first} % {second} % {third} % {fourth} % {first} % {second} % {third} % {fourth} % {first} % {second} % {third} % {fourth} % {first} % {second} % {third} % {fourth}I had this things That you could type uo right. But it didn‘t sing . So I said goodnight.
过程错误：
ex8.rb:3:in `%‘: key{first} not found (KeyError)
from ex8.rb:3:in `<main>‘
one two three four
ex8.rb:5:in `%‘: key{first} not found (KeyError)
from ex8.rb:5:in `<main>‘
提示说是：在使用formatter格式字符串时，没有找到其中的first标签，是Key的问题。
然后检查第一行输出中，first标签是否写对。
扩展：将原来的最后一个输出的双引号换成单引号
代码
formatter = "% {first} % {second} % {third} % {fourth}"puts formatter % { first: ‘I had this things‘, second: ‘That you could type uo right.‘, third: "But it didn‘t sing ." , fourth: ‘So I said goodnight.‘}
结果：
[ufindme@ufindme rubywork]$ ruby ex8-2.rb I had this things That you could type uo right. But it didn‘t sing . So I said goodnight.
曾有错误提示：
ex8-2.rb:6: syntax error, unexpected tIDENTIFIER, expecting ‘}‘
third: "But it didn"t sing ." ,
^
ex8-2.rb:6: syntax error, unexpected tSTRING_BEG, expecting ‘(‘
third: "But it didn"t sing ." ,
^
ex8-2.rb:7: syntax error, unexpected tCONSTANT, expecting end-of-input
fourth: "So I said goodnight."
错误的原因是：在双引号“”里面放了个双引号，是的后面那个双引号单独出现报错
后面将第一行的双引号改成单引号 后，还是可以正常显示，显示一样的结果。
LRTHW练习八