Paredit.clj

paredit in clojure, tailored for clojure

"coordinates" for build tools

##maven/ivy: org.lpetit paredit.clj 0.13.0.STABLE001

##lein/cake: [org.lpetit/paredit.clj "0.13.0.STABLE001"]

Dependencies

• Clojure 1.2
• Clojure contrib 1.2
• 0.0.9.STABLE001 of Laurent's fork of Christophe Grand's parsley

Design notes

##A central multimethod paredit.core/paredit, whose signature is:

    ([:paredit-command parsetree {:keys [:text :offset :length]})

• :paredit-command is one of the currently accepted commands, see the content of the var paredit.core-commands/paredit-commands for the whole list
• parsetree is the result of applying paredit.parser/parse to :text's value
• :text's value is the text corresponding to parsetree
• :offset is the current position of the caret in the text
• :length is the length of the current selection, or 0 if no selection

and which returns:

    {:keys [:text :offset :length] ({:keys [:text :offset :length]} & more) :modifs}   

• :text's value is the text resulting from applying the command
• :offset's value is the new offset of the caret
• :length's value is the new length of the selection
• :modifs's value is a sequence of deltas to apply to the original text in order to obtain the resulting text, and for each element in :modif's value ** :offset's value is the start offset of the text to replace ** :length's value is the length of the text to replace ** :text's value is the text to insert

##parsetree is a datastructure returned by invoking the function paredit.parser/parse on the source code:

    (paredit.parser/parse "(some source code)\n(foo :bar baz")

The result of paredit.parser/parse is a datastructure following clojure.core/xml conventions : :tag is used to name a parsetree node, :content is used to list children of a parsetree node. parsetree terminals are always java.lang.Strings.

Usage example

##Require the namespace
user=>(require 'paredit.core) ; automatically requires paredit.parser as well nil ##Send the source code to the parser user=>(def parse-tree (paredit.parser/parse "(foo bar)")) #'user/parse-tree

"raise sexp" example

    user=>(paredit.core/paredit :paredit-raise-sexp parse-tree {:text "(foo bar)" :offset 5 :length 0}) ; Let's raise "bar" over "(foo bar)"
    {:modifs ({:offset 0, :length 9, :text "bar"}), :text "bar", :offset 0, :length 0}

Note that the result provides the fully replaced text, while you also have a list of deltas to apply to the original text if this better suits your needs

"split expression" example

    user=>(paredit.core/paredit :paredit-split-sexp parse-tree {:text "(foo bar)" :offset 5 :length 0}) ; Let's raise "bar" over "(foo bar)"
    {:modifs ({:offset 4, :length 1, :text ") ("}), :text "(foo) (bar)", :offset 5, :length 0}