Hi everyone, I am new to Fantom. I recently started picking up learning Fantom and wanted to implement the Unix "strings" utility in Fantom. The utility reads a file (which can possibly be a binary file) into a buffer (sys::MemBuf). It iterates through the bytes in the file (using Buf.get(index)). The problem I am facing is this: how do I find if the byte I have read is a printable character?

I could not use java.lang.Character, as all the isXXX methods take a character, not an Int.

For sake of simplicity, we can assume that even though the file is binary, the characters that can possibly in that file are only ASCII. So its enough if I check only one byte to be printable or not.

Thank you for your help. Roy

What version of JVM do you use? java.lang.Character has methods taking int (like isLetterOrDigit(int codePoint)) marked as since 1.5.

Hi vkuzkokov, When I attempted to use that, I got the following error: C:\Users\roy\fantom\helloworld.fan(37,17): Ambiguous call isLetterOrDigit(sys::Int)

Do you mean isAlphaNum?

Exactly. Thats what I was looking for. Appreciate your help.

I didn't expect that method to be a part of Int :-(

Yeah, it's a quirky feature(?) of Fantom, but the Int class is shared between integers and unicode codepoints.

This is how it works in a few other languages, too. If I recall correctly, Erlang and (old?) Ruby do this.

Once you know where to look, it's not so hard, though.

btw,'isAlphaNum' is only a subset of the printable characters.