read_filter_lines {seekr} | R Documentation |
Read and Filter Matching Lines in Text Files
Description
Reads lines from a set of text files and returns only the lines that match a specified regular expression pattern. The function processes each file one-by-one to maintain memory efficiency, making it suitable for reading large files. Files that cannot be read (due to warnings or errors) are skipped with a warning.
If verbosity is enabled via seekr.verbose = TRUE
and the session is interactive,
the function reports progress.
Usage
read_filter_lines(files, pattern, ...)
Arguments
files |
A character vector of files to search (only for |
pattern |
A regular expression pattern used to match lines. |
... |
Additional arguments passed to |
Details
Files are processed sequentially to minimize memory usage, especially when working with
large files. Only the lines matching the pattern
are retained for each file.
If a file raises a warning or an error during reading, it is silently skipped and contributes an empty entry to the result lists.
Value
A list with two elements:
line_number
A list of integer vectors giving the line numbers of matching lines, one per file.
line
A list of character vectors containing the matched lines, one per file.