translation approved by the author instead of in the original English.
\1f
+File: xemacs.info, Node: Lisp Indent, Next: C Indent, Prev: Multi-line Indent, Up: Grinding
+
+Customizing Lisp Indentation
+----------------------------
+
+ The indentation pattern for a Lisp expression can depend on the
+function called by the expression. For each Lisp function, you can
+choose among several predefined patterns of indentation, or define an
+arbitrary one with a Lisp program.
+
+ The standard pattern of indentation is as follows: the second line
+of the expression is indented under the first argument, if that is on
+the same line as the beginning of the expression; otherwise, the second
+line is indented underneath the function name. Each following line is
+indented under the previous line whose nesting depth is the same.
+
+ If the variable `lisp-indent-offset' is non-`nil', it overrides the
+usual indentation pattern for the second line of an expression, so that
+such lines are always indented `lisp-indent-offset' more columns than
+the containing list.
+
+ Certain functions override the standard pattern. Functions whose
+names start with `def' always indent the second line by
+`lisp-body-indention' extra columns beyond the open-parenthesis
+starting the expression.
+
+ Individual functions can override the standard pattern in various
+ways, according to the `lisp-indent-function' property of the function
+name. (Note: `lisp-indent-function' was formerly called
+`lisp-indent-hook'). There are four possibilities for this property:
+
+`nil'
+ This is the same as no property; the standard indentation pattern
+ is used.
+
+`defun'
+ The pattern used for function names that start with `def' is used
+ for this function also.
+
+a number, NUMBER
+ The first NUMBER arguments of the function are "distinguished"
+ arguments; the rest are considered the "body" of the expression.
+ A line in the expression is indented according to whether the
+ first argument on it is distinguished or not. If the argument is
+ part of the body, the line is indented `lisp-body-indent' more
+ columns than the open-parenthesis starting the containing
+ expression. If the argument is distinguished and is either the
+ first or second argument, it is indented twice that many extra
+ columns. If the argument is distinguished and not the first or
+ second argument, the standard pattern is followed for that line.
+
+a symbol, SYMBOL
+ SYMBOL should be a function name; that function is called to
+ calculate the indentation of a line within this expression. The
+ function receives two arguments:
+ STATE
+ The value returned by `parse-partial-sexp' (a Lisp primitive
+ for indentation and nesting computation) when it parses up to
+ the beginning of this line.
+
+ POS
+ The position at which the line being indented begins.
+
+ It should return either a number, which is the number of columns of
+ indentation for that line, or a list whose first element is such a
+ number. The difference between returning a number and returning a
+ list is that a number says that all following lines at the same
+ nesting level should be indented just like this one; a list says
+ that following lines might call for different indentations. This
+ makes a difference when the indentation is computed by `C-M-q'; if
+ the value is a number, `C-M-q' need not recalculate indentation
+ for the following lines until the end of the list.
+
+\1f
+File: xemacs.info, Node: C Indent, Prev: Lisp Indent, Up: Grinding
+
+Customizing C Indentation
+-------------------------
+
+ Two variables control which commands perform C indentation and when.
+
+ If `c-auto-newline' is non-`nil', newlines are inserted both before
+and after braces that you insert and after colons and semicolons.
+Correct C indentation is done on all the lines that are made this way.
+
+ If `c-tab-always-indent' is non-`nil', the <TAB> command in C mode
+does indentation only if point is at the left margin or within the
+line's indentation. If there is non-whitespace to the left of point,
+<TAB> just inserts a tab character in the buffer. Normally, this
+variable is `nil', and <TAB> always reindents the current line.
+
+ C does not have anything analogous to particular function names for
+which special forms of indentation are desirable. However, it has a
+different need for customization facilities: many different styles of C
+indentation are in common use.
+
+ There are six variables you can set to control the style that Emacs C
+mode will use.
+
+`c-indent-level'
+ Indentation of C statements within surrounding block. The
+ surrounding block's indentation is the indentation of the line on
+ which the open-brace appears.
+
+`c-continued-statement-offset'
+ Extra indentation given to a substatement, such as the then-clause
+ of an `if' or body of a `while'.
+
+`c-brace-offset'
+ Extra indentation for lines that start with an open brace.
+
+`c-brace-imaginary-offset'
+ An open brace following other text is treated as if it were this
+ far to the right of the start of its line.
+
+`c-argdecl-indent'
+ Indentation level of declarations of C function arguments.
+
+`c-label-offset'
+ Extra indentation for a line that is a label, case, or default.
+
+ The variable `c-indent-level' controls the indentation for C
+statements with respect to the surrounding block. In the example:
+
+ {
+ foo ();
+
+the difference in indentation between the lines is `c-indent-level'.
+Its standard value is 2.
+
+ If the open-brace beginning the compound statement is not at the
+beginning of its line, the `c-indent-level' is added to the indentation
+of the line, not the column of the open-brace. For example,
+
+ if (losing) {
+ do_this ();
+
+One popular indentation style is that which results from setting
+`c-indent-level' to 8 and putting open-braces at the end of a line in
+this way. Another popular style prefers to put the open-brace on a
+separate line.
+
+ In fact, the value of the variable `c-brace-imaginary-offset' is
+also added to the indentation of such a statement. Normally this
+variable is zero. Think of this variable as the imaginary position of
+the open brace, relative to the first non-blank character on the line.
+By setting the variable to 4 and `c-indent-level' to 0, you can get
+this style:
+
+ if (x == y) {
+ do_it ();
+ }
+
+ When `c-indent-level' is zero, the statements inside most braces
+line up exactly under the open brace. An exception are braces in column
+zero, like those surrounding a function's body. The statements inside
+those braces are not placed at column zero. Instead, `c-brace-offset'
+and `c-continued-statement-offset' (see below) are added to produce a
+typical offset between brace levels, and the statements are indented
+that far.
+
+ `c-continued-statement-offset' controls the extra indentation for a
+line that starts within a statement (but not within parentheses or
+brackets). These lines are usually statements inside other statements,
+like the then-clauses of `if' statements and the bodies of `while'
+statements. The `c-continued-statement-offset' parameter determines
+the difference in indentation between the two lines in:
+
+ if (x == y)
+ do_it ();
+
+The default value for `c-continued-statement-offset' is 2. Some
+popular indentation styles correspond to a value of zero for
+`c-continued-statement-offset'.
+
+ `c-brace-offset' is the extra indentation given to a line that
+starts with an open-brace. Its standard value is zero; compare:
+
+ if (x == y)
+ {
+
+with:
+
+ if (x == y)
+ do_it ();
+
+If you set `c-brace-offset' to 4, the first example becomes:
+
+ if (x == y)
+ {
+
+ `c-argdecl-indent' controls the indentation of declarations of the
+arguments of a C function. It is absolute: argument declarations
+receive exactly `c-argdecl-indent' spaces. The standard value is 5 and
+results in code like this:
+
+ char *
+ index (string, char)
+ char *string;
+ int char;
+
+ `c-label-offset' is the extra indentation given to a line that
+contains a label, a case statement, or a `default:' statement. Its
+standard value is -2 and results in code like this:
+
+ switch (c)
+ {
+ case 'x':
+
+If `c-label-offset' were zero, the same code would be indented as:
+
+ switch (c)
+ {
+ case 'x':
+
+This example assumes that the other variables above also have their
+default values.
+
+ Using the indentation style produced by the default settings of the
+variables just discussed and putting open braces on separate lines
+produces clear and readable files. For an example, look at any of the C
+source files of XEmacs.
+
+\1f
File: xemacs.info, Node: Matching, Next: Comments, Prev: Grinding, Up: Programs
Automatic Display of Matching Parentheses
Move to beginning of current or previous statement (`fortran-
previous-statement').
-\1f
-File: xemacs.info, Node: Fortran Indent, Next: Fortran Comments, Prev: Fortran Motion, Up: Fortran
-
-Fortran Indentation
--------------------
-
- Special commands and features are available for indenting Fortran
-code. They make sure various syntactic entities (line numbers, comment
-line indicators, and continuation line flags) appear in the columns
-that are required for standard Fortran.
-
-* Menu:
-
-* Commands: ForIndent Commands. Commands for indenting Fortran.
-* Numbers: ForIndent Num. How line numbers auto-indent.
-* Conv: ForIndent Conv. Conventions you must obey to avoid trouble.
-* Vars: ForIndent Vars. Variables controlling Fortran indent style.
-
-\1f
-File: xemacs.info, Node: ForIndent Commands, Next: ForIndent Num, Prev: Fortran Indent, Up: Fortran Indent
-
-Fortran Indentation Commands
-............................
-
-`<TAB>'
- Indent the current line (`fortran-indent-line').
-
-`M-<LFD>'
- Break the current line and set up a continuation line.
-
-`C-M-q'
- Indent all the lines of the subprogram point is in
- (`fortran-indent-subprogram').
-
- <TAB> is redefined by Fortran mode to reindent the current line for
-Fortran (`fortran-indent-line'). Line numbers and continuation markers
-are indented to their required columns, and the body of the statement
-is independently indented, based on its nesting in the program.
-
- The key `C-M-q' is redefined as `fortran-indent-subprogram', a
-command that reindents all the lines of the Fortran subprogram
-(function or subroutine) containing point.
-
- The key `M-<LFD>' is redefined as `fortran-split-line', a command to
-split a line in the appropriate fashion for Fortran. In a non-comment
-line, the second half becomes a continuation line and is indented
-accordingly. In a comment line, both halves become separate comment
-lines.
-
-\1f
-File: xemacs.info, Node: ForIndent Num, Next: ForIndent Conv, Prev: ForIndent Commands, Up: Fortran Indent
-
-Line Numbers and Continuation
-.............................
-
- If a number is the first non-whitespace in the line, it is assumed
-to be a line number and is moved to columns 0 through 4. (Columns are
-always counted from 0 in XEmacs.) If the text on the line starts with
-the conventional Fortran continuation marker `$', it is moved to column
-5. If the text begins with any non whitespace character in column 5,
-it is assumed to be an unconventional continuation marker and remains
-in column 5.
-
- Line numbers of four digits or less are normally indented one space.
-This amount is controlled by the variable `fortran-line-number-indent',
-which is the maximum indentation a line number can have. Line numbers
-are indented to right-justify them to end in column 4 unless that would
-require more than the maximum indentation. The default value of the
-variable is 1.
-
- Simply inserting a line number is enough to indent it according to
-these rules. As each digit is inserted, the indentation is recomputed.
-To turn off this feature, set the variable
-`fortran-electric-line-number' to `nil'. Then inserting line numbers
-is like inserting anything else.
-
-\1f
-File: xemacs.info, Node: ForIndent Conv, Next: ForIndent Vars, Prev: ForIndent Num, Up: Fortran Indent
-
-Syntactic Conventions
-.....................
-
- Fortran mode assumes that you follow certain conventions that
-simplify the task of understanding a Fortran program well enough to
-indent it properly:
-
- * Two nested `do' loops never share a `continue' statement.
-
- * The same character appears in column 5 of all continuation lines.
- It is the value of the variable `fortran-continuation-char'. By
- default, this character is `$'.
-
-If you fail to follow these conventions, the indentation commands may
-indent some lines unaesthetically. However, a correct Fortran program
-will retain its meaning when reindented even if the conventions are not
-followed.
-
-\1f
-File: xemacs.info, Node: ForIndent Vars, Prev: ForIndent Conv, Up: Fortran Indent
-
-Variables for Fortran Indentation
-.................................
-
- Several additional variables control how Fortran indentation works.
-
-`fortran-do-indent'
- Extra indentation within each level of `do' statement (the default
- is 3).
-
-`fortran-if-indent'
- Extra indentation within each level of `if' statement (the default
- is 3).
-
-`fortran-continuation-indent'
- Extra indentation for bodies of continuation lines (the default is
- 5).
-
-`fortran-check-all-num-for-matching-do'
- If this is `nil', indentation assumes that each `do' statement
- ends on a `continue' statement. Therefore, when computing
- indentation for a statement other than `continue', it can save
- time by not checking for a `do' statement ending there. If this
- is non-`nil', indenting any numbered statement must check for a
- `do' that ends there. The default is `nil'.
-
-`fortran-minimum-statement-indent'
- Minimum indentation for Fortran statements. For standard Fortran,
- this is 6. Statement bodies are always indented at least this
- much.
-
-\1f
-File: xemacs.info, Node: Fortran Comments, Next: Fortran Columns, Prev: Fortran Indent, Up: Fortran
-
-Comments
---------
-
- The usual Emacs comment commands assume that a comment can follow a
-line of code. In Fortran, the standard comment syntax requires an
-entire line to be just a comment. Therefore, Fortran mode replaces the
-standard Emacs comment commands and defines some new variables.
-
- Fortran mode can also handle a non-standard comment syntax where
-comments start with `!' and can follow other text. Because only some
-Fortran compilers accept this syntax, Fortran mode will not insert such
-comments unless you have specified to do so in advance by setting the
-variable `comment-start' to `"!"' (*note Variables::).
-
-`M-;'
- Align comment or insert new comment (`fortran-comment-indent').
-
-`C-x ;'
- Applies to nonstandard `!' comments only.
-
-`C-c ;'
- Turn all lines of the region into comments, or (with arg) turn
- them back into real code (`fortran-comment-region').
-
- `M-;' in Fortran mode is redefined as the command
-`fortran-comment-indent'. Like the usual `M-;' command, it recognizes
-an existing comment and aligns its text appropriately. If there is no
-existing comment, a comment is inserted and aligned.
-
- Inserting and aligning comments is not the same in Fortran mode as in
-other modes. When a new comment must be inserted, a full-line comment
-is inserted if the current line is blank. On a non-blank line, a
-non-standard `!' comment is inserted if you previously specified you
-wanted to use them. Otherwise a full-line comment is inserted on a new
-line before the current line.
-
- Non-standard `!' comments are aligned like comments in other
-languages, but full-line comments are aligned differently. In a
-standard full-line comment, the comment delimiter itself must always
-appear in column zero. What can be aligned is the text within the
-comment. You can choose from three styles of alignment by setting the
-variable `fortran-comment-indent-style' to one of these values:
-
-`fixed'
- The text is aligned at a fixed column, which is the value of
- `fortran-comment-line-column'. This is the default.
-
-`relative'
- The text is aligned as if it were a line of code, but with an
- additional `fortran-comment-line-column' columns of indentation.
-
-`nil'
- Text in full-line columns is not moved automatically.
-
- You can also specify the character to be used to indent within
-full-line comments by setting the variable `fortran-comment-indent-char'
-to the character you want to use.
-
- Fortran mode introduces two variables `comment-line-start' and
-`comment-line-start-skip', which do for full-line comments what
-`comment-start' and `comment-start-skip' do for ordinary text-following
-comments. Normally these are set properly by Fortran mode, so you do
-not need to change them.
-
- The normal Emacs comment command `C-x ;' has not been redefined. It
-can therefore be used if you use `!' comments, but is useless in
-Fortran mode otherwise.
-
- The command `C-c ;' (`fortran-comment-region') turns all the lines
-of the region into comments by inserting the string `C$$$' at the front
-of each one. With a numeric arg, the region is turned back into live
-code by deleting `C$$$' from the front of each line. You can control
-the string used for the comments by setting the variable
-`fortran-comment-region'. Note that here we have an example of a
-command and a variable with the same name; the two uses of the name
-never conflict because in Lisp and in Emacs it is always clear from the
-context which one is referred to.
-
projects / chise / xemacs-chise.git / blobdiff