fix overwriting a binding to a function to be const (#702)

Author: KristofferC

.github/workflows/ci.yml

@@ -40,7 +40,7 @@ jobs:
           version: ${{ matrix.julia-version }}
           arch: ${{ matrix.julia-arch }}
       - name: Cache artifacts
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         env:
           cache-name: cache-artifacts
         with:

src/GLib/gtype.jl

@@ -168,7 +168,7 @@ function get_itype_decl(iname::Symbol, gtyp::GType, cm)
     piface_decl = get_itype_decl(piname, parent, cm)
     quote
         if $(QuoteNode(iname)) in keys(gtype_abstracts)
-            $(esc(iname)) = gtype_abstracts[$(QuoteNode(iname))]
+            const $(esc(iname)) = gtype_abstracts[$(QuoteNode(iname))]
         else
             $piface_decl
             abstract type $(esc(iname)) <: $(esc(piname)) end