chickadee » srfi-14 » char-set:punctuation

ASCII has 23 punctuation characters:

 !"#%&'()*,-./:;?@[\]_{}

Note that the nine ASCII characters $+<=>^`|~ are not punctuation. They are "symbols."

In Unicode, a punctuation character is any character that has one of the punctuation categories in the Unicode character database (P*).

Some Unicode punctuation characters: