正则表达式仅用于替换括号外的特定字符

Question

我正在寻找正则表达式（最好是 in R），它可以用 say 替换（任意数量的）特定字符;say;;但仅当文本字符串内的括号内不存在时()。

注意： 1. 括号内也可能存在多个替换字符

2.数据/向量中没有嵌套括号

例子

• text;othertext 替换为 text;;othertext
• 但text;other(texttt;some;someother);more要替换为text;;other(texttt;some;someother);;more. （即;仅在外部()被替换文本替换）

如果需要澄清，我会尝试解释

in_vec <- c("abcd;ghi;dfsF(adffg;adfsasdf);dfg;(asd;fdsg);ag", "zvc;dfasdf;asdga;asd(asd;hsfd)", "adsg;(asdg;ASF;DFG;ASDF;);sdafdf", "asagf;(fafgf;sadg;sdag;a;gddfg;fd)gsfg;sdfa")

in_vec
#> [1] "abcd;ghi;dfsF(adffg;adfsasdf);dfg;(asd;fdsg);ag"
#> [2] "zvc;dfasdf;asdga;asd(asd;hsfd)"             
#> [3] "adsg;(asdg;ASF;DFG;ASDF;);sdafdf"           
#> [4] "asagf;(fafgf;sadg;sdag;a;gddfg;fd)gsfg;sdfa"

预期输出（手动计算）

[1] "abcd;;ghi;;dfsF(adffg;adfsasdf);;dfg;;(asd;fdsg);;ag" 
[2] "zvc;;dfasdf;;asdga;;asd(asd;hsfd)"             
[3] "adsg;;(asdg;ASF;DFG;ASDF;);;sdafdf"            
[4] "asagf;;(fafgf;sadg;sdag;a;gddfg;fd)gsfg;;sdfa"

Answer 1

你可以用gsub与;(?![^(]*\\))：

gsub(";(?![^(]*\\))", ";;", in_vec, perl=TRUE)
#[1] "abcd;;ghi;;dfsF(adffg;adfsasdf);;dfg;;(asd;fdsg);;ag"
#[2] "zvc;;dfasdf;;asdga;;asd(asd;hsfd)"                   
#[3] "adsg;;(asdg;ASF;DFG;ASDF;);;sdafdf"                  
#[4] "asagf;;(fafgf;sadg;sdag;a;gddfg;fd)gsfg;;sdfa"       

;finds ;, (?!).. Negative Lookahead (在它不匹配时进行替换), [^(].. 一切但不是(,*重复前面的 0 到 n 次, \\).. 流过).

或者

gsub(";(?=[^)]*($|\\())", ";;", in_vec, perl=TRUE)
#[1] "abcd;;ghi;;dfsF(adffg;adfsasdf);;dfg;;(asd;fdsg);;ag"
#[2] "zvc;;dfasdf;;asdga;;asd(asd;hsfd)"                   
#[3] "adsg;;(asdg;ASF;DFG;ASDF;);;sdafdf"                  
#[4] "asagf;;(fafgf;sadg;sdag;a;gddfg;fd)gsfg;;sdfa"       

;finds ;, (?=).. Positive Lookahead (在匹配时进行替换), [^)].. 除不匹配外的所有内容),*重复前面的 0 到 n 次, ($|\\().. match end$或(.

或者使用gregexpr和regmatches提取和之间的部分(并)在不匹配的子字符串中进行替换：

x <- gregexpr("\\(.*?\\)", in_vec)  #Find the part between ( and )
mapply(function(a, b) {
  paste(matrix(c(gsub(";", ";;", b), a, ""), 2, byrow=TRUE), collapse = "")
}, regmatches(in_vec, x), regmatches(in_vec, x, TRUE))
#[1] "abcd;;ghi;;dfsF(adffg;adfsasdf);;dfg;;(asd;fdsg);;ag"
#[2] "zvc;;dfasdf;;asdga;;asd(asd;hsfd)"                   
#[3] "adsg;;(asdg;ASF;DFG;ASDF;);;sdafdf"                  
#[4] "asagf;;(fafgf;sadg;sdag;a;gddfg;fd)gsfg;;sdfa"       

但所有这些都只适用于简单的开(闭)组合。