Precision Editing for S-expressions
Vim script
Latest commit 471970b Dec 20, 2016 @frangio frangio committed with don't break undo with delimiter insertion

README.markdown

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Introduction

Vim-sexp brings the Vim philosophy of precision editing to S-expressions.

Requirements

  • Vim 7.3+

  • vim-repeat (optional)

    Enables use of the . command for repeating change operations in vim-sexp, as well as repeating builtin operations with vim-sexp's text objects.

Definitions

A COMPOUND FORM is a region of text delimited by a pair of ( and ), [ and ], or { and }.

A STRING is a contiguous region of text whose syntax name matches the Vim pattern \vstring|regex|pattern.

A COMMENT is a region of text whose syntax name matches the Vim pattern comment. Line comments that are indented but on successive lines are considered to be a single comment.

MACRO CHARACTERS are the special set of leading characters expanded by a Lisp reader at read-time. These differ by language, and default to Scheme's macro character set in an unknown FileType.

An ELEMENT is the

  • current STRING if the cursor is in a STRING
  • current COMMENT if the cursor is in a COMMENT
  • current COMPOUND FORM if the cursor is on a paired structural bracket
  • current sequence of MACRO CHARACTERS and the following ELEMENT if the cursor is on a MACRO CHARACTER
  • current contiguous sequence of non-whitespace, non-bracket characters otherwise

An ELEMENT always includes any leading MACRO CHARACTERS.

Mappings

All default mappings can be changed via the g:sexp_mappings variable. Every mapping is available as a <Plug> mapping, which may be used for any purpose.

Users who desire more explicit, opt-in configuration should refer to :help sexp-explicit-mappings.

Comprehensive documentation is available at :help vim-sexp. The following is a brief summary.

Text Object Selections (visual, operator-pending)

Text object selections refer to text around the cursor.

  • The af and if objects select COMPOUND FORMS.
  • The aF and iF objects select top-level COMPOUND FORMS.
  • The as and is objects select STRINGS.
  • The ae and ie objects select ELEMENTS.

Text Object Motions (normal, visual, operator-pending)

Text object motions move the cursor in normal mode, extend selections in visual mode, and refer to text defined by the movement of the cursor in operator-pending mode.

  • The ( and ) motions move the cursor to the nearest paired structural bracket.
  • The <M-b> and <M-w> motions move the cursor ELEMENT-wise, ending on an element head. Analogous to builtin b and w motions.
  • The g<M-e> and <M-e> motions move the cursor ELEMENT-wise, ending on an element tail. Analogous to builtin ge and e motions.
  • The [[ and ]] motions move the cursor to an adjacent top-level ELEMENT.
  • The [e and ]e mappings select an adjacent ELEMENT.

Indent Commands (normal)

  • == indents the current COMPOUND FORM without moving the cursor
  • =- indents the current top-level COMPOUND FORM without moving the cursor

Wrap Commands (normal, visual)

Wrap commands wrap the current COMPOUND FORM, ELEMENT, or visual selection and place the cursor at the head or tail of the newly created COMPOUND FORM.

If g:sexp_insert_after_wrap is set (true by default), insert mode is entered after wrapping.

  • <LocalLeader>i and <LocalLeader>I wrap the current COMPOUND FORM with ( and ).
  • <LocalLeader>[ and <LocalLeader>] wrap the current COMPOUND FORM with [ and ].
  • <LocalLeader>{ and <LocalLeader>} wrap the current COMPOUND FORM with { and }.
  • <LocalLeader>W and <LocalLeader>w wrap the current ELEMENT with ( and ).
  • <LocalLeader>e[ and <LocalLeader>e] wrap the current ELEMENT with [ and ].
  • <LocalLeader>e{ and <LocalLeader>e} wrap the current ELEMENT with { and }.

List Manipulation (normal, visual)

List manipulation commands change the structure of COMPOUND FORMS. If these commands are called from visual mode, the selection is used in place of the current COMPOUND FORM or ELEMENT.

  • <LocalLeader>@ splices the current COMPOUND FORM into its parent.
  • <LocalLeader>o raises the current COMPOUND FORM to replace the enclosing COMPOUND FORM.
  • <LocalLeader>O raises the current ELEMENT to replace the enclosing COMPOUND FORM.
  • <M-k> and <M-j> swap the position of the current COMPOUND FORM with a sibling ELEMENT.
  • <M-h> and <M-l> swap the position of the current ELEMENT with a sibling ELEMENT.
  • <M-S-j> and <M-S-k> emit the terminal ELEMENTS of the current COMPOUND FORM.
  • <M-S-h> and <M-S-l> capture adjacent ELEMENTS into the current COMPOUND FORM.

The last two commands are also known as barfage and slurpage in paredit.el.

Cursor Insertion (normal)

  • <LocalLeader>h inserts the cursor at the head of the current COMPOUND FORM
  • <LocalLeader>l inserts the cursor at the tail of the current COMPOUND FORM

If inserting at the head, a space is conditionally appended after the opening bracket so that any typed characters will be separated from the next element.

Insert Mode Mappings (insert)

Vim-sexp does intelligent bracket and double quote insertion like paredit.el. Unlike ParEdit, deletion of brackets that would cause an imbalance is not prevented, except in the limited case of <BS> below.

  • (, [, and { produce a closing bracket and also insert spaces as necessary to separate the new COMPOUND FORM from adjacent non-compound ELEMENTS.
  • ), ], and } insert closing brackets when the corresponding opening bracket is unpaired. If the opening bracket is paired, jump to the next paired instance of the closing bracket.
  • " inserts a pair of double quotes, unless the cursor is currently in a STRING.
  • <BS> deletes an adjacent pair of (), [], {}, and "" when deleting the opening bracket or quote. Normal backspace otherwise.

These insert mode mappings can be disabled with:

let g:sexp_enable_insert_mode_mappings = 0