Component bblscm_versiontag [Package bblscm]

Provide versioning information for the bbl package group. More...

Outline

• Purpose
• Description
  • Usage

Purpose:

Provide versioning information for the bbl package group.

See also:

Component bblscm_version

Description:

This component provides versioning information for the bbl package group. The BBL_VERSION macro that is supplied can be used for conditional-compilation based on bbl version information. The following usage example illustrates this basic capability.

Usage:

At compile time, the version of BBL can be used to select an older or newer way to accomplish a task, to enable new functionality, or to accommodate an interface change. For example, if the name of a function changes (a rare occurrence, but potentially disruptive when it does happen), the impact on affected code can be minimized by conditionally calling the function by its old or new name using conditional compilation. In the following, the #if preprocessor directive compares BBL_VERSION (i.e., the latest BBL version, excluding the patch version) to a specified major and minor version composed using the BBL_MAKE_VERSION macro:

  #if BBL_VERSION > BBL_MAKE_VERSION(1, 3)
      // Call 'newFunction' for BBL versions later than 1.3.
      int result = newFunction();
  #else
      // Call 'oldFunction' for BBL version 1.3 or earlier.
      int result = oldFunction();
  #endif