JGREP(1)

💖 JGREP(1) — the jgrep manual, but make it cute 💖

okay bestie, sit down, hydrate, and let me tell you about jgrep — a command line tool and API for parsing JSON documents based on logical expressions. she's giving filter queen, she's giving query energy, and honestly? she ate. 🍓

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✨ SYNOPSIS ✨

jgrep <expression> [options]

like that's it. that's the whole vibe. you hand her an expression, she hands you truth. 🫶

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🌸 DESCRIPTION 🌸

so here's the tea: jgrep can be used for filtering the contents of a JSON (JavaScript Object Notation) file after having parsed it. no cap. 🔥

and the expressions? they're doing the most, in the best way:

• they can help with testing for the presence or absence of certain elements in the file 💅
• they can also test the values of certain elements ⭐

it's giving "I don't read the whole JSON, I interrogate it". main character behavior fr fr.

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👑 OPTIONS 👑

every single flag, exactly as she is. no skipping, no summarizing, we respect the craft. 💜

• -s, --simple <FIELD...> — greps the JSON and only returns the value of the field(s) specified. just the value, nothing extra, minimalism slay ✨
• -c, --compat — returns the JSON in its non-pretty flat form. compact. efficient. lowkey iconic 🎀
• -n, --stream — specify continuous input. she keeps listening, she's patient like that 🦋
• -f, --flatten — flatten the results as much as possible. squish. 🫶
• -i, --input <FILENAME> — target JSON file to use as input. If this option is not specified, jgrep will expect to find JSON content on the standard input. iykyk 📥
• -q, --quiet — quiet; don't write to stdout. Exit with zero status if match found. she says nothing and still wins 💀
• -v, --verbose — verbose output that will list a document if it fails to parse. she's gonna tell you exactly which doc fumbled 🙈
• --start <FIELD> — starts the grep at a specific key in the document. skip to the good part 🌈
• --slice <RANGE> — a range of the form 'n' or 'n..m', indicating which documents to extract from the final output. portion control bestie 🍓

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🧚 EXPRESSIONS 🧚

JGrep uses the following logical symbols to define expressions. memorize them, they're your new love language 💖

and

[statement] and [statement]

Evaluates to true if both statements are true. both. BOTH. no half measures 💅

or

[statement] and [statement]

Evaluates true if either statement is true. (yes, that's literally what the page says up there, we're keeping it verbatim, no editing the source material ✋)

not | !

! [statement]
not [statement]

Inverts the value of statement. flip it, reverse it, turn it upside down 🔄

+

+[value]

Returns true if value is present in the json document. presence check, she's here, she's accounted for ✨

-

-[value]

Returns true if value is not present in the json doument. absence check — if she's not in the building, that's a true 🚫

( and )

(expression1) and expression2

Performs the operations inside the perentheses first. parentheses are the VIP section, they go first, periodt 👑

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🌈 STATEMENTS 🌈

A statement is defined as some value in a JSON document compared to another value.

Available comparison operators are =, <, >, <= and >=

that's it, that's the toolbox, and honestly she does so much with so little 💜

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⭐ EXAMPLES ⭐

Given the following JSON document:

{"foo":1, "bar":null}

the following are examples of valid expressions:

+foo

returns true ✅

-bar

returns false ❌

+foo and !(foo=2)

returns true ✅

!(foo>=2 and bar=null) or !(bar=null)

returns true ✅

see how she's thinking? logical. precise. obsessed. 🧠✨

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🎀 AUTHOR 🎀

Gabriel Filion

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and that's the whole page bestie, no crumbs left. this was the jgrep(1) manual, dated 2020 — go forth and filter your JSON with main character energy. bye love you, drink water 💖🦋🌸💅🫶