why do we need set causal_mask =True in clip

[liuxiaoqun]

prompt is a sentence ,we don't need to predict next token in prompt, is there a question to see the right tokens?
x = self.attention(x, causal_mask=True)

[RohollahHS]

This my question as well.

[ninaddaithankar]

I had the same query. This is the answer I found in the CLIP paper by OpenAI:

"Masked self-attention was used in the text encoder to preserve the ability to initialize with a pre-trained language model or add language modeling as an auxiliary objective, though exploration of this is left as future work."

Paper: https://arxiv.org/pdf/2103.00020