Let $M$ be an $m$ dimensional manifold and $N$ be an $n$-dimensional manifold *with boundary*. Suppose also that the topology on $N$ can be described by a metric. Thus, the set $C(M,N)$ can be endowed with the topology of uniform convergence on compacta.

Intuitively is seems that every continuous function $f:M\rightarrow N$ should be able to be approximated by continuous functions of the form $g:M\rightarrow\operatorname{int}(N)$; where $N=\operatorname{int}(N)\cup \partial N$, $\partial N$ denotes the boundary of $N$ and $\operatorname{int}(N)$ the $n$-dimensional manifold defined by removing $N's$ boundary points but is this formally true? I.e. is it true that

$$ \overline{C(M,\operatorname{int}(N)} = C(M,N)? $$

Prototype construction: Let $N=[0,b)$ then any function $f$ can be approximated by: $$ f_n= \min\left(\frac1{n},f\right) , $$ of course, these are continuous but not smooth *(since we don't need smoothness this is a non-issue). I expect this type of construction should generalize...