rules-make.md

simple-indentation-rules-make --- Simple Indention

Table of Contents

• rules-make --- Simple Indention
  • General Termins
  • Run and Check Rules
  • :predicate
  • :check-on-prev-line
  • :check-on-prev-code-line
  • :check-on-prev-code-line
  • :on-current-or-previous-line
  • :on-current-or-previous-code-line
  • :on-current-or-previous-text-line
  • :on-keywords
  • :on-keywords-in-code

General Termins

Rule is just type, which has predicate and indent-func. Predicate is just function which no take arguments and return t, when current line needs to indent. "Line needs to indent" is means, that current line needs to run indent-func. Indent Function (indent-func) is function, which no take arguments and just change current line (by idea).

Indention function defaults to simple function, which no take arguments and no return values and don't change Emacs' state

Predicate defaults to function always return t.

For create use:

(simple-indentation-rules-make
 :predicate (lambda () (eq (% (line-number-at-pos) 2) 0))
 :indent-func (lambda () (insert "   ")))

For details see below!

Run and Check Rules

For this simple-indentation has 3 functions:

• simple-indentation-rules-indent-current-line-p
• simple-indentation-rules-call-indent-function
• simple-indentation-rules-indent-current-line-with-func-p

simple-indentation-rules-indent-current-line-p take rule, and return t, when this rule needs to indent current line.

simple-indentation-rules-call-indent-function take rule, and call indent-func of this rule.

simple-indentation-rules-indent-current-line-with-func-p is more high level function, take list of rules, search first rule needs to indent current line, and run indent-func of this rule.

Mangaing with Predicates

:predicate

Each rule can has some predicates. If rule has (1+) predicates, then main predicate will just return t, when on of some predicates return t.

Example

(simple-indentation-rules-make
 :predicate (lambda () (eq (% (line-number-at-pos) 2) 0))
 :predicate (lambda () (eq (% (line-number-at-pos) 3) 0)))

:check-on-prev-line

This is just goto previous line before check predicate, if goto previous line is failed, then predicate will return nil.

NOTE: add :check-on-prev-line after predicate, before you want goto previous line

(simple-indentation-rules-make
 :predicate (lambda () (eq (% (line-number-at-pos) 2) 0))
 :check-on-prev-line)

:check-on-prev-code-line

This is work as :check-on-prev-line, but insead of goto previous line, this kewords go to previous no empty line.

:check-on-prev-code-line

This is work as :check-on-prev-line, but insead of goto previous line, this kewords go to previous code (no commentary and string, empty) line.

:on-current-or-previous-line

If predicate get nil in current line, then go to previous line and check predicate here.

NOTE: add :on-current-or-previous-line after predicate, for which you may be need to go to previous line.

Example:

(simple-indentation-rules-make
 :on-chars "!"
 :on-current-or-previous-line)

:on-current-or-previous-code-line

If predicate get nil in current line, then go to previous code line (see :check-on-prev-code-line) and check predicate here.

NOTE: add :on-current-or-previous-code-line after predicate, for which you may be need to go to previous line.

Example:

(simple-indentation-rules-make
 :on-chars "!"
 :on-current-or-previous-code-line)

:on-current-or-previous-text-line

If predicate get nil in current line, then go to previous text line (see :check-on-prev-text-line) and check predicate here.

NOTE: add :on-current-or-previous-text-line after predicate, for which you may be need to go to previous line.

Example:

(simple-indentation-rules-make
 :on-chars "!"
 :on-current-or-previous-text-line)

:on-keywords

Make predicate, which return t, when current line has one of passed keywords.

This keywords needs to required folowed argument - list of strings (keywords).

NOTE: In a lot of cases you should use :on-keywords-in-code for ignore keywords in commentaries

Example (super simple):

(simple-indentation-rules-make
 :on-keywords "end" "endif" "endfor")

Example 2 (with :check-on-prev-code-line):

(simple-indentation-rules-make
 :on-keywords "end" "endif" "endfor"
 :check-on-prev-code-line)

Very important, that :check-on-prev-code-line go after :on-keywords in section about :check-on-prev-line I say, that this keyword needs to put after predicate, you must keep in mind, that :on-keywords is also "predicate"

:on-keywords-in-code

Make predicate, which return t, when current line, ignoring comments and strings, has one of passed keywords.

This keywords needs to required folowed argument - list of strings (keywords).

Example (super simple):

(simple-indentation-rules-make
 :on-keywords-in-code "end" "endif" "endfor")

Example 2 (with :check-on-prev-code-line):

(simple-indentation-rules-make
 :on-keywords-in-code "end" "endif" "endfor"
 :check-on-prev-code-line)

Very important, that :check-on-prev-code-line go after :on-keywords in section about :check-on-prev-line I say, that this keyword needs to put after predicate, you must keep in mind, that :on-keywords-in-code is also "predicate"

:on-chars

Make predicate, which return t, when current line, has one of chars of passed string.

This keywords needs to required folowed argument - string (chars).

NOTE: In a lot of cases you should use :on-chars-in-code for ignore chars in commentaries

Example (super simple):

(simple-indentation-rules-make
 :on-chars "{}")

Example 2 (with :check-on-prev-code-line):

(simple-indentation-rules-make
 :on-chars "{}
 :check-on-prev-code-line)

Very important, that :check-on-prev-code-line go after :on-chars in section about :check-on-prev-line I say, that this keyword needs to put after predicate, you must keep in mind, that :on-chars is also "predicate"

:on-chars-in-code

Make predicate, which return t, when current line, ignoring comments and strings, has one of chars of passed string.

This keywords needs to required folowed argument - string (chars).

Example (super simple):

(simple-indentation-rules-make
 :on-chars-in-code "{}")

Example 2 (with :check-on-prev-code-line):

(simple-indentation-rules-make
 :on-chars-in-code "{}"
 :check-on-prev-code-line)

Very important, that :check-on-prev-code-line go after :on-chars in section about :check-on-prev-line I say, that this keyword needs to put after predicate, you must keep in mind, that :on-chars-in-code is also "predicate"

Mangaing with indent-funcs

:indent-func

:indent-func set indent-func of current rule to passed function. Each rule can't have some indent-func, so if you use :indent-func some times, that indent-func of rule will be last passed indent-func

Example:

(simple-indentation-rules-make
 :indent-func (lambda () (insert "    ")))

:add-indent

Set indent-func of current rule to function on value of simple-indentation-increment-indent-level-function, this variable automatic set after run one of functions defines by simple-indentation-define-for-major-mode, by idea this function just insert one-indent for current major mode.

(simple-indentation-rules-make
 :add-indent)

:deindent

Set indent-func of current rule to function on value of simple-indentation-decrement-indent-level-function, this variable automatic set after run one of functions defines by simple-indentation-define-for-major-mode, by idea this function chop one-indent when current line start with one-indent.

(simple-indentation-rules-make
 :deindent)