mango - Create a man page from a Go package’s source file’s documentation.
mango [-help] [-import import_path] [-name name] [-version version] [-manual manual] [-package package_name] [-section Sections] [-include Includes] [package-directory|package-files]
Mango generates man files from the source of a Go package. If the package is main, it creates a section 1 man page. Otherwise, it creates a section 3 man page.
Mango is a tool similar to godoc(1) and uses the same conventions and information so that documentation will look the same in both. Further, Mango uses no special markup. The text is formatted by simple rules, described in FORMATTING below. The input is the comments and AST of the Go package. The output is raw troff markup (compatiable with nroff and groff) dumped to stdout for pipelining, see EXAMPLES.
For section 1 man pages, Mango bases the OPTIONS section on the use of flag(3) and a special comment. It takes
var file = flag.String("source", "", "Set source file")
var toggle = flag.Bool("t", false, "Toggle mode")
var banner = flag.Bool("title", "Hello", "Set banner")
-banner = Hello
Extraction of this information will not work if the flag package is renamed on import and it can only extract flags defined with flag.Type and not those defined with flag.TypeVar in the init() function. Additional information may be given with a comment like
//Usage: %name %flags [optional-arg] required-arg
The "Usage:" part is mandatory. %name and %flags (or %flag) exist only to make the intent clear to a reader unfamiliar with mango(1). Both may be used together, each may be used separately, and neither are required.
Format package in current directory with nroff:
mango | nroff -man > name.section
Format package in current directory as a ps file with groff:
mango | groff -man > name.section.ps
Format package in current directory as a pdf:
mango | groff -man | ps2pdf - name.section.pdf
Format ogle(3), and ogle(1), which exist in the same directory:
mango $GOROOT/src/pkg/exp/ogle | nroff -man > ogle.3
mango -package main $GOROOT/src/pkg/exp/ogle | nroff -man > ogle.1
Format your package in a makefile:
mango -import $TARG $GOFILES | nroff -man > name.section
An all caps word on a line by itself, followed and preceded by a blank like denotes a new section.
Two consecutive newlines start a new paragraph.
Indented paragraphs, with one tab or four spaces, maintain their relative indentation (a uniform, initial indent is ignored) and no additional formatting is applied
Words beginning with a hyphen are assumed to be command line switches, and they, including the hypen, are bolded. Words ending with (.) where . is a valid (even if obscure) man page section are formatted with the word but not the (.) in bold. In addition, each word is added to the SEE ALSO section.
If no directory or files are specified, Mango uses the current working directory. If there are multiple packages in the input directory, any package named 'documentation’ is used as the package level documentation. If there is no 'documentation’ package or there are still multiple packages after taking 'documentation’ out of play, Mango will use the package with the same name as the input directory. If this is incorrect, or you wish to generate man pages for multiple packages in one directory you can select them individually with the -package flag.
The name of the man page is the name of the package for section 3 man pages and the name of the file that contains func main() for section 1 man pages. This can be overridden with the -name flag, but only for section 1 pages.
For man 3 pages, the import path defaults to the name of the package. It can be overridden with the -import flag and the
If the -version flag is not used, Mango searches the AST for a const or var declaration named Version. Failing that, it uses today’s date as the version.
If the -manual flag is not used, it defaults to "User Commands" for man 1 pages and to "Go Packages" for man 3 pages, respectively.
Sections in the comments, or specified by the -include or -sections flags, are in the same order as they appear in the comments, with the exception that DIAGNOSTICS, ENVIRONMENT, and FILES section appear first, and in that order; and that HISTORY appears after the SEE ALSO section.
In man 1 pages, the user-defined sections appear between the OPTIONS and BUGS sections. In man 3 pages, they appear after the DESCRIPTION section.
|Specify import path|
|Specify name of man page|
|Specify the manual: see man-pages(7)|
|Select package to use if there are multiple packages in a directory|
|Generate sections from a comma-seperated list of filenames. Each section will be named after the file name that contains it (_ will be replaced by a space). The contents of each file will be formatted by the same rules as if they were extracted from comments. To include preformatted sections see -include. You cannot override SYNOPSIS, OPTIONS, BUGS or SEE ALSO.|
|Generate sections from a comma-seperated list of filenames. Each section will be named after the file name that contains it (_ will be replaced by a space). The contents of each file will be included as-is. To let mango do the formatting use -section.|
Quotation marks are all wrong in postscript output.
Need to special case flag.Var to make it format properly.
No way to group short/long name option pairs.
Does not render RHS of consts or vars for section 3.