Component bdlscm_versiontag [Package bdlscm]

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

Outline

• Purpose
• Description
  • Usage

Purpose:

Provide versioning information for the bdl package group.

See also:

Component bdlscm_version

Description:

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

Note that since bdl is always released in lock-step with bsl, they share common versioning, and the BDL_VERSION will always equal the BSL_VERSION.

Usage:

At compile time, the version of BDL 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 BDL_VERSION (i.e., the latest BDL version, excluding the patch version) to a specified major and minor version composed using the BSL_MAKE_VERSION macro:

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