Boost Statechart vs. Meta State Machine

Question

Apparently boost contains two separate libraries for state machines: Statechart and Meta State Machine (MSM). The taglines give very similar descriptions:

• Boost.St

Answer 1

As there seems to be much interest, please allow me to give my (obviously biased) opinion, which should therefore be taken with a grain of salt:

• MSM is much faster
• MSM requires no RTTI or anything virtual
• MSM has a more complete UML2 support (for example internal transitions, UML-conform orthogonal regions)
• MSM offers a descriptive language (actually several). For example, using the eUML front-end, a transition can be described as Source + Event [Guard] / Action == Target
• MSM will make your compiler suffer for bigger state machines, so you will need a pretty recent compiler (g++ >= 4.x, VC >= 9)

You can make yourself a better opinion by looking for comments posted during the review of MSM. This subject was much discussed on the developer list.