New type FunctionHandle with RW support in v7 and HDF formats

Author: foreverallama

src/MAT.jl

@@ -37,7 +37,7 @@ include("MAT_v4.jl")
 using .MAT_HDF5, .MAT_v5, .MAT_v4, .MAT_subsys
 
 export matopen, matread, matwrite, @read, @write
-export MatlabStructArray, MatlabClassObject, MatlabOpaque, MatlabTable
+export MatlabStructArray, MatlabClassObject, MatlabOpaque, MatlabTable, FunctionHandle
 
 # Open a MATLAB file
 const HDF5_HEADER = UInt8[0x89, 0x48, 0x44, 0x46, 0x0d, 0x0a, 0x1a, 0x0a]

src/MAT_HDF5.jl

@@ -324,7 +324,9 @@ function m_read(g::HDF5.Group, subsys::Subsystem)
         if haskey(attr, sparse_attr_matlab)
             return read_sparse_matrix(g, mattype)
         elseif mattype == "function_handle"
-            # TODO: fall through for now, will become a Dict
+            if haskey(attr, object_decode_attr_matlab) && read_attribute(g, object_decode_attr_matlab)==1
+                is_object = true
+            end
         else
             if haskey(attr, object_decode_attr_matlab) && read_attribute(g, object_decode_attr_matlab)==2
                 # I think this means it's an old object class similar to mXOBJECT_CLASS in MAT_v5

src/MAT_types.jl

@@ -41,6 +41,7 @@ export MatlabClassObject
 export MatlabOpaque, convert_opaque
 export MatlabTable
 export ScalarOrArray
+export FunctionHandle
 
 const ScalarOrArray{T} = Union{T, AbstractArray{T}}
 
@@ -176,7 +177,7 @@ function Base.:(==)(m1::MatlabStructArray{N}, m2::MatlabStructArray{N}) where {N
 end
 
 function Base.isapprox(m1::MatlabStructArray, m2::MatlabStructArray; kwargs...)
-    return isequal(m1.class, m2.class) && issetequal(m1.names, m2.names) && 
+    return isequal(m1.class, m2.class) && issetequal(m1.names, m2.names) &&
     key_based_isapprox(m1.names, m1, m2; kwargs...)
 end
 
@@ -300,6 +301,13 @@ struct EmptyStruct
 end
 class(m::EmptyStruct) = ""
 
+"""
+Function Handles which are stored as structs
+"""
+struct FunctionHandle
+    d::Dict{String,Any}
+end
+
 """
     MatlabClassObject(
         d::Dict{String, Any},
@@ -357,6 +365,8 @@ function convert_struct_array(d::AbstractDict{String,Any}, class::String="")
     else
         if isempty(class)
             return d
+        elseif class == "function_handle"
+            return FunctionHandle(d)
         else
             return MatlabClassObject(d, class)
         end

src/MAT_v5.jl

@@ -28,7 +28,7 @@
 module MAT_v5
 using CodecZlib, HDF5, SparseArrays
 import Base: read, write, close
-import ..MAT_types: MatlabStructArray, MatlabClassObject, MatlabTable
+import ..MAT_types: MatlabStructArray, MatlabClassObject, MatlabTable, FunctionHandle
 
 using ..MAT_subsys
 
@@ -325,6 +325,11 @@ function read_string(f::IO, swap_bytes::Bool, dimensions::Vector{Int32})
     data
 end
 
+function read_function_handle(f::IO, swap_bytes::Bool, subsys::Subsystem)
+    data = read_matrix(f, swap_bytes, subsys)[2] # read_matrix returns (var_name, data)
+    return FunctionHandle(data)
+end
+
 function read_opaque(f::IO, swap_bytes::Bool, subsys::Subsystem)
     type_name = String(read_element(f, swap_bytes, UInt8))
     classname = String(read_element(f, swap_bytes, UInt8))
@@ -375,7 +380,7 @@ function read_matrix(f::IO, swap_bytes::Bool, subsys::Subsystem)
     elseif class == mxCHAR_CLASS && length(dimensions) <= 2
         data = read_string(f, swap_bytes, dimensions)
     elseif class == mxFUNCTION_CLASS
-        data = read_matrix(f, swap_bytes, subsys)
+        data = read_function_handle(f, swap_bytes, subsys)
     elseif class == mxOPAQUE_CLASS
         data = read_opaque(f, swap_bytes, subsys)
     else

test/read.jl

@@ -222,12 +222,12 @@ end
 # test reading file containing Matlab function handle, table, and datetime objects
 let objtestfile = "function_handles.mat"
     vars = matread(joinpath(dirname(@__FILE__), "v7.3", objtestfile))
-    @test "sin" in keys(vars)
-    @test typeof(vars["sin"]) == Dict{String, Any}
-    @test Set(keys(vars["sin"])) == Set(["function_handle", "sentinel", "separator", "matlabroot"])
-    @test "anonymous" in keys(vars)
-    @test typeof(vars["anonymous"]) == Dict{String, Any}
-    @test Set(keys(vars["anonymous"])) == Set(["function_handle", "sentinel", "separator", "matlabroot"])
+    @test haskey(vars, "sin")
+    @test haskey(vars, "anonymous")
+    @test vars["sin"] isa FunctionHandle
+    @test vars["anonymous"] isa FunctionHandle
+    @test Set(keys(vars["sin"].d)) == Set(["function_handle", "sentinel", "separator", "matlabroot"])
+    @test Set(keys(vars["anonymous"].d)) == Set(["function_handle", "sentinel", "separator", "matlabroot"])
 end
 
 for format in ["v7", "v7.3"]