Document and export continuous_events and discrete_events

docs/src/basics/Events.md

@@ -58,6 +58,10 @@ be handled via more [general functional affects](@ref func_affects).
 
 Finally, multiple events can be encoded via a `Vector{Pair{Vector{Equation}, Vector{Equation}}}`.
 
+Given an `AbstractSystem`, one can fetch its continuous events, and the continuous events of any
+subsystem inside of it using the `continuous_events(::AbstractSystem)` method, returning a vector
+of `ModelingToolkit.SymbolicContinuousCallback` objects.
+
 ### Example: Friction
 
 The system below illustrates how continuous events can be used to model Coulomb
@@ -221,6 +225,10 @@ equations can either all change unknowns (i.e. variables) or all change
 parameters, but one cannot currently mix unknown variable and parameter changes within one
 individual event.
 
+Given an `AbstractSystem`, one can fetch its discrete events, and the discrete events of any
+subsystem inside of it using the `discrete_events(::AbstractSystem)` method, returning a vector
+of `ModelingToolkit.SymbolicDiscreteCallback` objects.
+
 ### Example: Injecting cells into a population
 
 Suppose we have a population of `N(t)` cells that can grow and die, and at time

src/ModelingToolkit.jl

@@ -35,7 +35,7 @@ using PrecompileTools, Reexport
     using RecursiveArrayTools
 
     using SymbolicIndexingInterface
-    export independent_variables, unknowns, parameters, full_parameters
+    export independent_variables, unknowns, parameters, full_parameters, continuous_events, discrete_events
     import SymbolicUtils
     import SymbolicUtils: istree, arguments, operation, similarterm, promote_symtype,
                           Symbolic, isadd, ismul, ispow, issym, FnType,

src/systems/callbacks.jl

@@ -138,6 +138,11 @@ function namespace_callback(cb::SymbolicContinuousCallback, s)::SymbolicContinuo
         namespace_affects(affects(cb), s))
 end
 
+"""
+    continuous_events(sys::AbstractSystem)
+
+Returns a vector of all the `continuous_events` in an abstract system and its component subsystems. 
+"""
 function continuous_events(sys::AbstractSystem)
     obs = get_continuous_events(sys)
     filter(!isempty, obs)
@@ -234,6 +239,11 @@ SymbolicDiscreteCallbacks(cb::SymbolicDiscreteCallback) = [cb]
 SymbolicDiscreteCallbacks(cbs::Vector{<:SymbolicDiscreteCallback}) = cbs
 SymbolicDiscreteCallbacks(::Nothing) = SymbolicDiscreteCallback[]
 
+"""
+    discrete_events(sys::AbstractSystem)
+
+Returns a vector of all the `discrete_events` in an abstract system and its component subsystems. 
+"""
 function discrete_events(sys::AbstractSystem)
     obs = get_discrete_events(sys)
     systems = get_systems(sys)