我试图拆分一个包含两个条目的字符串，每个条目都有特定的格式:
active site/region)，后面跟一个:
His, Glu/nucleotide-binding motif A)，后跟,
下面是我要拆分的字符串:
string <- "active site: His, Glu,region: nucleotide-binding motif A,"
这就是我迄今为止所try 的.除了两个空的子字符串外，它生成所需的输出.
unlist(str_extract_all(string, ".*?(?=,(?:\\w+|$))"))
[1] "active site: His, Glu" "" "region: nucleotide-binding motif A"
[4] ""
我如何go 掉空的子字符串？
得到空字符串是因为.*?也可以匹配一个空字符串，其中断言(?=,(?:\\w+|$))为真
在匹配:之前，可以使用否定字符类排除匹配冒号或逗号
[^:,\n]+:.*?(?=,(?:\w|$))
Explanation
[^:,\n]+个匹配1+字符，而不是: ,或换行符:匹配冒号.*?尽可能匹配任何字符(?= Positive lookahead, assert that what is directly to the right from the current position:
,场比赛(?:\w|$)匹配单个单词字符，或断言字符串的结尾)关闭前瞻R demo.com/r/3lycNW/1" rel="nofollow noreferrer">Regex demo | R demo
string <- "active site: His, Glu,region: nucleotide-binding motif A,"
unlist(str_extract_all(string, "[^:,\\n]+:.*?(?=,(?:\\w|$))"))
输出
[1] "active site: His, Glu" "region: nucleotide-binding motif A"