Grape

Grape is a syntax-aware grep-like utility for Clojure code. It allows you to search for code patterns using Clojure data structures.

Command-line

$ grape [options] <pattern> [<file> ...]

For example, to find all usages of map called with three arguments in grape’s own code:

grape --unindent '(map $ $ $)' src

Output:

src/grape/impl/match.clj:
29:(map match?
        trees
        patterns)

src/grape/cli.clj:
137:(map #(when (= %1 %2) %1) prefix line-prefix)

Options:

• -c, --count: show the total matches count and exit.
• -F, --no-filenames: by default, grape shows the matching filenames when run on multiple files. This option disables that.
• -u, --unindent: un-indent matches.
• --line-numbers first|all|none: control line numbers. The default is first, i.e. only the first line of each match is prefixed by its line number. all shows all line numbers; none remove them.
• -n, --all-line-numbers: alias for --line-numbers all
• -N, --no-line-numbers: alias for --line-numbers none
• --inline: force matches on one line

Run grape --help to show all options.

Install

Either get the standalone binary (faster) or a jar from the Releases page.

If you have Homebrew, you can install it like so:

brew install bfontaine/utils/grape

Library

(require '[grape.core :as g])

(def my-code (slurp "myfile.clj"))

;; Find all occurrences of map called with three arguments
(g/find-codes my-code (g/pattern "(map $ $ $)"))

;; Find all occurrences of (condp = ...)
(g/find-codes my-code (g/pattern "(condp = $&)"))

;; Find all occurrences of `if` with no `else` clause
(g/find-codes my-code (g/pattern "(if $ $)"))
; => ({:match "(if …)", :meta {…}}, …)

Matches are map with a :match key that contains a string with the matching code and a :meta key with line/column metadata which you can use to locate the code in your file.

Patterns

A pattern is any valid Clojure expression. It can contain some special symbols that are interpreted as wildcards.

Comments, whitespaces, and discard reader macros (#_) are ignored when matching.

Wildcards

• $: any expression.
• $&: any number of expressions, including zero. (f $&) matches (f), (f 1), (f 1 2), etc.
• $string, $list, etc: any expression of the given type.

See the full patterns documentation.

Wildcards can be combined: #{$ $&} matches a set with at least one element.

License

Copyright © 2019-2020 Baptiste Fontaine

This program and the accompanying materials are made available under the terms of the Eclipse Public License 2.0 which is available at http://www.eclipse.org/legal/epl-2.0.

This Source Code may also be made available under the following Secondary Licenses when the conditions for such availability set forth in the Eclipse Public License, v. 2.0 are satisfied: GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version, with the GNU Classpath Exception which is available at https://www.gnu.org/software/classpath/license.html.