该文件名为testFile.txt,并包含以下行：

section 0; state 0; not needed
= start section 1 =
state 1; needed
= end section 1 =
section 2; state 2; not needed

我的单行是

cat testFile.txt | perl6 -ne ' state $x = 0; say "$x--> "; if $_ ~~ m/ "start" / { $x=1; }; if $x == 1 { .say; }; if $_ ~~ m/ "end" / { $x = 2; }'

并且输出显示$x = 0没有进行初始化：

Use of uninitialized value $x of type Any in string context.
Methods .^name,.perl,.gist,or .say can be used to stringify it to something meaningful.
  in block  at -e line 1
--> 
Use of uninitialized value of type Any in numeric context
  in block  at -e line 1
Use of uninitialized value $x of type Any in string context.
Methods .^name,or .say can be used to stringify it to something meaningful.
  in block  at -e line 1
--> 
= start section 1 =
1--> 
state 1; needed
1--> 
= end section 1 =
2--> 
2-->