After reading tkrajacic’s hint, I pasted your code into macvim–an open source computer programming editor–and there were some weird vim codes appearing between each letter of the line flagged with the error:
Then I used HexFiend–an open source hex editor–to look at the text. A hex editor will show you every byte. Some text editors, e.g. Xcode, will skip bytes that they don’t understand or include them but not display anything for that byte–not even a space. If I tell HexFiend to interpret the bytes as ASCII text, it looks like this:
If I tell the hex editor to interpret the bytes as UTF-8, it looks like this:
The dots mean that there are three bytes before the ‘v’, but that those bytes contain integers that are not valid UTF-8 character codes. The extra bytes before each character contain the same three integers. Here are the integers in hex format:
Some program somewhere reads those integers–probably for formatting, e.g. the codes could be an instruction to display/print the following character in bold. Was that code bolded in the text you copied? I’ve seen similar garbage when people write code in MS Word, then copy and paste the text into their program.