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GNU Info (forms)Format DescriptionThe Format Description ********************** The variable `forms-format-list' specifies the format of the data in the data file, and how to convert the data for display in Forms mode. Its value must be a list of Forms mode "formatting elements", each of which can be a string, a number, a Lisp list, or a Lisp symbol that evaluates to one of those. The formatting elements are processed in the order they appear in the list. STRING A string formatting element is inserted in the forms "as is," as text that the user cannot alter. NUMBER A number element selects a field of the record. The contents of this field are inserted in the display at this point. Field numbers count starting from 1 (one). LIST A formatting element that is a list specifies a function call. This function is called every time a record is displayed, and its result, which must be a string, is inserted in the display text. The function should do nothing but returning a string. The function you call can access the fields of the record as a list in the variable `forms-fields'. SYMBOL A symbol used as a formatting element should evaluate to a string, number, or list; the value is interpreted as a formatting element, as described above. If a record does not contain the number of fields as specified in `forms-number-of-fields', a warning message will be printed. Excess fields are ignored, missing fields are set to empty. The control file which displays `/etc/passwd' file as demonstrated in the beginning of this manual might look as follows: ;; This demo visits `/etc/passwd'. (setq forms-file "/etc/passwd") (setq forms-number-of-fields 7) (setq forms-read-only t) ; to make sure (setq forms-field-sep ":") ;; Don't allow multi-line fields. (setq forms-multi-line nil) (setq forms-format-list (list "====== /etc/passwd ======\n\n" "User : " 1 " Uid: " 3 " Gid: " 4 "\n\n" "Name : " 5 "\n\n" "Home : " 6 "\n\n" "Shell: " 7 "\n")) When you construct the value of `forms-format-list', you should usually either quote the whole value, like this, (setq forms-format-list '( "====== " forms-file " ======\n\n" "User : " 1 (make-string 20 ?-) ... )) or quote the elements which are lists, like this: (setq forms-format-list (list "====== " forms-file " ======\n\n" "User : " 1 '(make-string 20 ?-) ... )) Forms mode validates the contents of `forms-format-list' when you visit a database. If there are errors, processing is aborted with an error message which includes a descriptive text. Note: Error Messages, for a detailed list of error messages. If no `forms-format-list' is specified, Forms mode will supply a default format list. This list contains the name of the file being visited, and a simple label for each field indicating the field number. automatically generated by info2www version 1.2.2.9 |