Alternative approach to #4270 without a staged function

base/abstractarray.jl

@@ -142,34 +142,28 @@ reshape(a::AbstractArray, dims::Int...) = reshape(a, dims)
 vec(a::AbstractArray) = reshape(a,length(a))
 vec(a::AbstractVector) = a
 
-function nextunsqueezeddim(dims, i)
-    while true
-        squeeze = false
-        for dim in dims
-            if dim == i
-                squeeze && error("squeezed dims must be unique")
-                squeeze = true
-            end
+argtail(x, rest...) = rest
+tail(x::Tuple) = argtail(x...)
+
+_sub(::(), ::()) = ()
+_sub(t::Tuple, ::()) = t
+_sub(t::Tuple, s::Tuple) = _sub(tail(t), tail(s))
+
+function squeeze(A::AbstractArray, dims::Dims)
+    for i in 1:length(dims)
+        1 <= dims[i] <= ndims(A) || error("squeezed dims must be in range [1, ndims(A)]")
+        size(A, dims[i]) == 1 || error("squeezed dims must all be size 1")
+        for j = 1:i-1
+            dims[j] == dims[i] && error("squeezed dims must be unique")
         end
-        !squeeze && return i
-        i += 1
     end
-end
-
-stagedfunction squeeze(A::AbstractArray, dims::Dims)
-    n = ndims(A)
-    quote
-        if !($(Expr(:&&, [:(1 <= dims[$i] <= $n) for i = 1:length(dims)]...)))
-            error("squeezed dims must be in range [1, ndims(A)]")
-        elseif !($(Expr(:&&, [:(size(A, dims[$i]) == 1) for i = 1:length(dims)]...)))
-            error("squeezed dims must all be size 1")
+    d = ()
+    for i = 1:ndims(A)
+        if !in(i, dims)
+            d = tuple(d..., size(A, i))
         end
-
-        dim_1 = nextunsqueezeddim(dims, 1)
-        $([:($(symbol("dim_$i")) = nextunsqueezeddim(dims, $(symbol("dim_$(i-1)"))+1)) for i = 2:n-length(dims)]...)
-
-        reshape(A, tuple($([:(size(A, $(symbol("dim_$i")))) for i = 1:n-length(dims)]...)))
     end
+    reshape(A, d::typeof(_sub(size(A), dims)))
 end
 
 squeeze(A::AbstractArray, dim::Integer) = squeeze(A, (int(dim),))