local variables with hashes

rubyonrails-talk
1

I have a question about using local variables as values for ruby hashes. I have to do a script that will gather meta data of video files in a fixed directory and store them in an array of hashes. The problem is that when I have collected the meta data to a hash called video and append this to the end of videos array all the hash entries are the same in the array. I assign the values to the hash and append to the videos array with this script block:

video["res_w"] = res_w video["res_h"] = res_h video["dur_h"] = dur_h video["dur_m"] = dur_m video["dur_s"] = dur_s video["dur_ms"] = dur_ms videos << video

All the local variables have been initialized as zeroes and when my loop retrieves another file for processing it reuses the local variables. The actual question is does the hash store a pointer to the local variable as its value? If it does is there a way to overwrite this behaviour or some way around it?

2

Pentti Laitinen wrote:

I have a question about using local variables as values for ruby hashes. I have to do a script that will gather meta data of video files in a fixed directory and store them in an array of hashes. The problem is that when I have collected the meta data to a hash called video and append this to the end of videos array all the hash entries are the same in the array. I assign the values to the hash and append to the videos array with this script block:

video["res_w"] = res_w video["res_h"] = res_h video["dur_h"] = dur_h video["dur_m"] = dur_m video["dur_s"] = dur_s video["dur_ms"] = dur_ms videos << video

All the local variables have been initialized as zeroes and when my loop retrieves another file for processing it reuses the local variables. The actual question is does the hash store a pointer to the local variable as its value? If it does is there a way to overwrite this behaviour or some way around it?

Integer hash values aren't stored as object references.

Perhaps your problem is that you're not re-initializing video to {} each time around the loop, so you're always updating a common video object.