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Comment by nescafe | Hacker News Reader

Find is overkill for this.

  for file in *.java; do
     [[ -f $file ]] || continue
     javac "$file"
  done

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This would avoid errors on the files with whitespaces, however it will also avoid compiling them. You cannot make the assumption that a file with a whitespace should not be compiled.

It will compile files with whitespaces. That's what [[]] is for.

No it won't, [[ -f $file ]] will fail and `continue` will be executed, moving on to the next iteration of the loop. Think of the different successive values the $file variable will have. At no point, will it hold the full name of the file at once.

I think you're confused. I just tried this in a few shells.

It works in Bash on Cygwin and OS X.

    touch "file with spaces"
    for f in *; do if [[ -f $f ]]; then echo file: $f; fi; done;

This echoes one line for "file with spaces".

Incorrect. Word splitting does not happen in [[ ]] tests. The only reason I had the [[ -f $file ]] || continue is to handle the case where there are no .java files, which will cause the for loop to iterate once with file set to '*.java'. i could have also used nullglob,but chose not to.

I realize that this is specifically for bash, but this won't work in zsh:

  % for blah in *.java; do echo $blah; done
  zsh: no matches found: *.java

That's just the zsh regex quirk; try quoting *.java.

What if "*.java" expands to something too large? Or is that only a relevant concern on the command line itself ("Argument list too long" error) and not within a script?

you need to doublequote $file on your second line:

      [[ -f "$file" ]] || continue

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