[julia-users] Curious behavior

[David Gleich]

Julia managed to surprise me today. I'm wondering how to understand what 
happens in this case and if it's a side effect of some design decision or 
syntax -- or a bug.

The following code executes without any errors

for i=1:5
    for j=1:5
        if i == j
            blah
        end
    end
end

and "blah" can be anything you want! I discovered this because I had 

for i=1:5
    for j=1:5
        if i == j
            contine # continue mis-spelled
        end
    end
end

This code executes and runs when pasted into the console or as part of a 
function in:

Julia-0.4 (in console and via ipython notebook), Julia-0.4.2 (on Juliabox) 
and Julia-0.5-dev (on Juliabox)

What I would have expected is some type of error such as "blah" is not 
defined, e.g.

julia> function myans()
         blah
       end
myans (generic function with 1 method)

julia> myans()
ERROR: UndefVarError: blah not defined
 in myans at none:2

It seems like this is likely some type of design implication because:

julia> function myans()
         blah
         1
       end
myans (generic function with 1 method)

julia> myans()
1

Any insights would be awesome for my own understanding!

Thanks,
David Gleich