An overview of the building module's role and abilities.

• §1. Prerequisites
• §2. Services for builders

§1. Prerequisites. The building module is a part of the Inform compiler toolset. It is presented as a literate program or "web". Before diving in:

• (a) It helps to have some experience of reading webs: see inweb for more.
• (b) The module is written in C, in fact ANSI C99, but this is disguised by the fact that it uses some extension syntaxes provided by the inweb literate programming tool, making it a dialect of C called InC. See inweb for full details, but essentially: it's C without predeclarations or header files, and where functions have names like Tags::add_by_name rather than just add_by_name.
• (c) This module uses other modules drawn from the compiler, and also uses a module of utility functions called foundation. For more, see A Brief Guide to Foundation (in foundation).

§2. Services for builders. This module is essentially middleware. It does none of the proactive business of compiling, but instead acts as a bridge to the low-level functions in the bytecode module, allowing them to be used with much greater ease.

In particular, Inter code is fundamentally a mass of inter_packages, which cross-reference each other using inter_symbols. But of course it cannot all be made simultaneously. What we need is a more flexible way to describe things in the Inter tree: both those which have already been made, and also those which are yet to be made. So:

                DEFINITELY MADE     PERHAPS NOT YET MADE
    PACKAGE     inter_package       package_request
    SYMBOL      inter_symbol        inter_name

So, for example, a package_request can represent /main/synoptic/kinds either before or after that package has been built. At some point the package ceases to be virtual and comes into being: this is called "incarnation".

And similarly for inter_name, which it would perhaps be more consistent to call a symbol_request.

§3. Since what is built by the code in this module is Inter code, which forms up into trees, the metaphor should perhaps be "garden", but in fact we call a context for making Inter a building_site.