fix(library/equations_compiler/structural_rec): bug at check_arg_type
fix(library/equations_compiler/structural_rec): bug at check_arg_type

leanprover/lean,johoelzl/lean,avigad/lean,soonhokong/lean-windows,Kha/lean,avigad/lean,soonhokong/lean-osx,Kha/lean,fgdorais/lean,soonhokong/lean-osx,dselsam/lean,leanprover-community/lean,Kha/lean,soonhokong/lean-osx,leanprover-community/lean,fgdorais/lean,avigad/lean,dselsam/lean,leanprover-community/lean,johoelzl/lean,digama0/lean,rlewis1988/lean,soonhokong/lean-osx,fpvandoorn/lean,leodemoura/lean,leodemoura/lean,leodemoura/lean,soonhokong/lean-windows,dselsam/lean,leanprover-community/lean,leanprover/lean,rlewis1988/lean,leanprover/lean,fgdorais/lean,fpvandoorn/lean,leodemoura/lean,digama0/lean,leodemoura/lean,johoelzl/lean,Kha/lean,fpvandoorn/lean,rlewis1988/lean,digama0/lean,rlewis1988/lean,johoelzl/lean,dselsam/lean,digama0/lean,rlewis1988/lean,avigad/lean,soonhokong/lean-windows,fpvandoorn/lean,digama0/lean,dselsam/lean,Kha/lean,fgdorais/lean,fpvandoorn/lean,leanprover-community/lean,soonhokong/lean-osx,fgdorais/lean,soonhokong/lean-windows,rlewis1988/lean,leodemoura/lean,digama0/lean,avigad/lean,johoelzl/lean,johoelzl/lean,Kha/lean,avigad/lean,leanprover/lean,leanprover/lean,fpvandoorn/lean,dselsam/lean,fgdorais/lean,leanprover-community/lean,soonhokong/lean-windows,leanprover/lean