Abstract

At the moment, there already is a preprocessor flag CT_NO_LEGACY_REACTIONS_26 introduced in Reaction.h, although it remains untested (at the moment, I am aware of at least one instance where toggling this flag will result in compilation errors). In order to ensure that the new framework introduced in #87 works without legacy support, the use of this preprocessor flag (or an additional CT_NO_LEGACY_26) could be extended to completely eliminate legacy reactions (as well as various CTI/XML tags).

The flag could be adopted in SCons

Motivation

Describe the need for the work being done:

• What problem is it trying to solve? ... ensure that changes introduced in 2.6 are feature complete and do not rely on legacy objects.
• Who is affected by the change? ... early adopters and developers
• Why is this a good solution? ... the preprocessor will allow for CI tests without legacy support prior to the 2.6 release; deprecated code is automatically marked. As 2.6 is the last release to include legacy features, this will add a layer ensuring that everything is ready for the transition to 3.0.

Alternatives

Just make sure that toggling the flag to change defaults works (while still adding a CI runner that covers this configuration).

Edit: Changes proposed in Cantera/cantera#1184 largely address this issue, as remaining 'hybrid' implementations no longer use legacy objects.