json Usage and options

Reads in a JSON file and quickly evaluates it.

Usage

json <filename> <evaluation string>

json only take two arguments. <filename> is the name of the file you wish to read into the program and interpret. <evaluation string> is a string containing valid JavaScript that is ran after loading the JSON object into memory. Memory is given the token $ to represent the JSON object and can be used literally in the string.

Examples

Example 1: Check the version on a package.json file

json package.json $.version

# Outputs:
#    1.0.2

Example 2: Loop through the keywords of a package and make them uppercase

This is useless in real life, but it gives you the gist of how to use the function. Note that we use console.log() to print out values.

json package.json '$.keywords.forEach(word => console.log(word.toUpperCase()))'

# Outputs:
#    BASH
#    TERMINAL
#    TOOLS

json also returns the value of expressions, so we could have done this instead:

json package.json '$.keywords.map(word => word.toUpperCase())'

# Outputs:
#    [ 'BASH', 'TERMINAL', 'TOOLS' ]