CLI Application

Installation

$ brew install yutanagano/tap/symscan-cli

You can also directly download precompiled binaries from the project releases page.

Usage

Tip

You can also view symscan’s inline help text with symscan --help.

Give symscan a list of strings, and it will tell you which ones are similar. By default, it will detect which strings are within one (Levenshtein) edit distance away from one another. Symscan reads its standard input stream and considers each line (delineated by newline characters) a separate string. A minimal example is below:

$ echo $'fizz\nfuzz\nbuzz\nfizzy' | symscan
1,2,1
1,4,1
2,3,1

As you can see, symscan outputs its result in plaintext to standard output. Each line in its output corresponds to a pair of similar strings that is detected. The first two numbers in each line is the (1-indexed) line numbers corresponding to the two similar input strings. The third and final number is the number of edits separating the two strings.

Options

To look for string pairs that are at most <k> edits away from each other, pass the option -d <k>:

$ echo $'fizz\nfuzz\nbuzz\nfizzy' | symscan -d 2
1,2,1
1,3,2
1,4,1
2,3,1
2,4,2

If you want the output to have 0-indexed line numbers as opposed to 1-indexed, pass the option -z:

$ echo $'fizz\nfuzz\nbuzz' | symscan -d 2 -z
0,1,1
0,2,2
0,3,1
1,2,1
1,3,2

If you want to limit your neighbor search to only allow substitutions, you can set the --hamming option. Note that in this case, input strings with different character lengths will never be considered neighbors.

$ echo $'fizz\nfuzz\nbuzz' | symscan -d 2 -z --hamming
0,1,1
0,2,2
1,2,1

Read from and write to files

To read input from input.txt and write to output.txt:

$ symscan input.txt > output.txt

or

$ < input.txt symscan > output.txt

or

$ cat input.txt | symscan > output.txt

Look for pairs across two string sets

To look strictly for strings in set_a.txt that are similar to strings in set_b.txt (ignores pairs within sets):

$ symscan set_a.txt set_b.txt > output.txt