Remove blockdiag

Author: odow

src/MOI_wrapper.jl

@@ -717,7 +717,41 @@ function Base.getindex(x::SDPBlock, i, j)
     end
 end
 
-include("blockdiag.jl")
+abstract type AbstractBlockMatrix{T} <: AbstractMatrix{T} end
+
+function nblocks end
+
+function block end
+
+function Base.size(bm::AbstractBlockMatrix)
+    n = mapreduce(
+        blk -> LinearAlgebra.checksquare(block(bm, blk)),
+        +,
+        1:nblocks(bm);
+        init = 0,
+    )
+    return (n, n)
+end
+
+function Base.getindex(bm::AbstractBlockMatrix, i::Integer, j::Integer)
+    (i < 0 || j < 0) && throw(BoundsError(i, j))
+    for k in 1:nblocks(bm)
+        blk = block(bm, k)
+        n = size(blk, 1)
+        if i <= n && j <= n
+            return blk[i, j]
+        elseif i <= n || j <= n
+            return 0
+        else
+            i -= n
+            j -= n
+        end
+    end
+    i, j = (i, j) .+ size(bm)
+    throw(BoundsError(i, j))
+end
+
+Base.getindex(A::AbstractBlockMatrix, I::Tuple) = getindex(A, I...)
 
 abstract type BlockMat <: AbstractBlockMatrix{Cdouble} end