@@ -52,7 +52,7 @@ For example, `some-command | grep ERROR` will print out only the lines of output
Implement `grep` (including 4 of its command-line flags) in Node.js.
Your `grep` will be invoked using `node grep.js [-i] [-r] [-v] [-z] pattern [files ...]`.
Your `grep` will be invoked using `npm run grep [-i] [-r] [-v] [-z] pattern [files ...]`.
The flags `-i`, `-r`, `-v`, and `-z` are described later.
A simple implementation of `grep` would read the entire input, loop over its lines, and print the lines that match the pattern.
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@@ -75,15 +75,15 @@ The values should be interpreted as follows:
If no filenames are given and `-r` is not used, the standard input (`process.stdin`) should be searched instead.
-`recursive` stores whether the flag `-r` was used.
If so, `files` are expected to be directories and are searched recursively.
For example, `node grep.js pattern -r dir1 dir2` searches all files in `dir1` and `dir2` (and all their subdirectories) for `pattern`.
For example, `npm run grep pattern -r dir1 dir2` searches all files in `dir1` and `dir2` (and all their subdirectories) for `pattern`.
If no directories are provided, the current directory (`.`) should be searched instead.
You can use the provided function `readdirRecursive()` to search each directory.
-`gunzip` stores whether the flag `-z` was used.
If so, all files are treated as [gzip](https://en.wikipedia.org/wiki/Gzip)ped text files and are unzipped before being searched.
For example, if `independence.txt` is compressed to `independence.txt.gz`, then `node grep.js -z ss independence.txt.gz` prints the same lines as `node grep.js ss independence.txt`.
For example, if `independence.txt` is compressed to `independence.txt.gz`, then `npm run grep -z ss independence.txt.gz` prints the same lines as `npm run grep ss independence.txt`.
Note that `-z` and `-r` can be used together.
-`ignoreCase` stores whether the flag `-i` was used.
If so, the pattern is case-insensitive, e.g. `node grep.js -i error` would match a line containing `error`, `ERROR`, or `ErRoR`.
If so, the pattern is case-insensitive, e.g. `npm run grep -i error` would match a line containing `error`, `ERROR`, or `ErRoR`.
You can use `RegExp(pattern, 'i')` to make a case-insensitive regular expression.
-`invert` stores whether the flag `-v` was used.
If so, the pattern specifies lines to *exclude*; only the lines that don't match the pattern are printed.
