Writing to specific lines in a File

[Chris Fullmer]

Lets say I have a file with 100 lines. I would like to open that file, and insert a line before line X (lets say line 50). Is that possible without loading the whole file into an array with readlines?

Chris

[Dan Rathbun]

Good question... never tried it.

You can set the current line via lineno=(), but I suspect these IO file functions (which File inherits,) are sequential files, and using puts() after setting the line, is likely to overwrite that line.

Perhaps you may wish to look in the standard Ruby Extended libs for a Random Access File extension ??

[Dan Rathbun]

OH !! Chris ... didn't realize this.. there's a TempFile manager class in the standard Ruby library.

Also there's the PStore class, which is like a file-based Hash.

There's also a "massive" CSV class.

[Chris Fullmer]

Awesome Dan, thanks! I'll go look into those.