Why '[, - \\]' matches '46', 'X', 'A',

Question

I am trying to break a string using strsplit(str, '[,-\\+]'), which means that anyone ',', '-' or '+'can be a delimiter. However, I found that this model also matches numbers and capital letters. Try

• grep('[,-\\]', 'X'), returns 1
• grep('[,-\\]', '46'), returns 1
• grep('[,-\\]', '-'), returns 1
• grep('[,-\\]', ','), returns 1

It seems to '[,-\\]'match all numbers, in capital letters, ','and '-'.

I just don’t understand why this is so.

Thanks for any input.

Answer 1

You need to use

strsplit(str, '[,+-]')

to divide by , +or -. If you need to add \for separation, use the '[,\\+-]'default TRE with the regex mechanism.

- ( , ) , . , '[,-\\]' , \:

, TRE ( perl=TRUE), . "[,-\\]" , PCRE , 4 .