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jello:tldr:b9cf0
This command is a combination of two commands: cat
and jello
.
The cat
command is used to read the contents of a file and outputs them to the terminal. In this case, ${file-json}
represents the name of a JSON file, and cat ${file-json}
is used to display the contents of that JSON file.
The jello
command is a command-line tool for manipulating JSON data. It allows you to perform various operations on JSON objects. In this command, the jello
command is used to apply a Python expression on the JSON data.
The Python expression, '[i.${key_name} for i in _]'
, is enclosed in single quotes within the jello
command. It is a list comprehension expression that is executed on the input JSON data represented by the _
symbol.
The expression [i.${key_name} for i in _]
loops through each object in the input JSON data (_
), extracts the value of the key specified by ${key_name}
, and creates a new list with those values.
For example, if the input JSON data contains objects with a key called name
, and ${key_name}
is replaced with name
, the expression [i.${key_name} for i in _]
will create a list of all the name
values from the input JSON data.
Overall, this command is used to extract specific values from a JSON file and display them in a list format.