A pattern declaration must be in a file called NAME.inweb which is inside a directory of plugins and templates, called NAME. The declaration should be written thus:

Language "NAME" {
	...
}

where the body ... consists of blank lines, or of any of the following, given in any order:

• based on: ENAME declares that the new pattern is based on an existing one called ENAME. For the pattern to be used, Inweb must be able to see that existing pattern somewhere: it will halt with an error if not. Any of the settings in this section (other than based on) will be taken from ENAME if the new pattern does not specify them.

• default range: RANGE tells Inweb how granular the weave of a multi-section web should be, by default. default range: sections means that each section should be woven to its own file. default range: chapters means that each chapter is in its own file, which presents all its sections in turn.

• format: FORMAT gives the fundamental kind of output being made. This must be one of those supported by Inweb:

  HTML  ePub  plain  TeX  TestingInweb
  

  ePub is the book format; plain is plain text; TeX is (plain) TeX; and TestingInweb should not be used except for its advertised purpose.

• block template: FILE tells Inweb not to read a file of this name from the template(s) that the current template is based on. This can only be used with template files like template-body.html. (It is less fuss to change the version of template-body.html: simply supply a replacement in the new template's directory. But if the idea is to not have the file at all, then this command is needed.)

• plugin: PNAME tells Inweb to include the plugin PNAME, which should be a subdirectory called PNAME of the pattern directory. It should contain asset files: see Asset Management.

• mathematics plugin: PNAME tells Inweb to include PNAME if and only if the weave includes any TeX mathematics formulae in commentary.

• footnotes plugin: PNAME tells Inweb to include PNAME if and only if the weave includes any use of footnotes in commentary.

• assets, followed by lines containing instructions on how to include files of various types, followed by an end line. See Asset Management.

• initial extension: .EXT is useful only when commands are supplied. See The Post-Weave.

• commands, followed by lines containing post-weave shell script commands, followed by an end line. See The Post-Weave.