TheFool

README

TheFool

TheFool is a simple command line csv combination program that can be used to merge, subtract and subset csv files.

Installation

From Release

Pre-built binaries for Windows and linux can be found on the releases page

From Source

building TheFool only requires a working go tool chain and can be done by running

git clone https://github.com/Grimmr/TheFool.git
cd TheFool
go build .

Usage

TheFool takes a single expression to evaluate and prints the resulting csv table to stdout.

Filenames

The most basic part of an expression is a filename. Filenames that contain spaces or that are the same as a reserved keyword (see Operators) need to be surrounded in quotes. Note that quotes are parsed out of expressions (like in bash) so the following are functionally identical

"a file.txt"
"a "file.txt
a" "file.txt
"a file".txt

Also keep in mind that some environments (like bash) will consume quotes before they reach TheFool and may need to be escaped.

Example usage

TheFool dogs.csv less myDogs.csv > notMyDogs.csv
TheFool dogs.csv or cats.csv
TheFool animals.csv less (birds.csv or dogs.csv)

Operators

Op	Usage	Header Semantics	Row Semantics	Row Multiplicity
and	<table> and <table>	Only headers that exist in both input tables are selected	Only common fields are considered. Only rows that exist in both input tables are selected.	either 1 or 0, duplicate rows are discarded
or	<table> or <table>	All headers from both inputs tables are selected	All rows from both tables are selected. Any fields added to a row are left empty.	either 1 or 0, duplicate rows are discarded
less	<table> less <table>	Only headers from the left hand input table are selected	Only common fields are considered. All rows that appear in the left hand input table less the rows that appear in the right hand table are selected.	Selected rows have the same multiplicity as in the left hand input table.
filter	<table> filter <table>	Only headers from the left hand input table are selected	Only common fields are considered. Only rows that exist in both input tables are selected.	Selected rows have the same multiplicity as in the left hand input table.
%	<table> % <number>	All headers from the input table are selected	Rows are selected randomly up to either <number> or the length of the input table whichever is smaller.	Multiplicity of a row is no more then it's multiplicity in the input table.
+	<table> + <table>	All headers from both inputs tables are selected	All rows from both tables are selected. Any fields added to a row are left empty.	The multiplicity of a selected row is exactly the sum of its multiplicities in the input tables
-	<table> - <table>	Only headers from the left hand input table are selected	Only common fields are considered. All rows that appear in the left hand input table less the rows that appear in the right hand table are selected.	Selected row multiplicity is calculated as their multiplicity in the left hand input table minus their multiplicity in the right hand input table.