Fix variable expansion on expressions.#107
Open
Krush206 wants to merge 4 commits intotcsh-org:masterfrom
Open
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
It's known variables expand earlier than expression evaluations. The procedure
would fail if
aisn't set. The correct behavior is to evaluate$?afirst, and, if expanded to zero, cancel further processing.This work remedies the issue by postponing variable expansions during expression evaluations. The function
Dfix1is used for I/O redirections, and fails if the expansion is null or, if not quoted, larger than one word/vector. I believe this behavior is fine.This work was also supposed to fix
$<expansions on pipes and redirections. I had some success with a fix, but ends up blocking the shell, making it unusable and uninterruptible.