This should give us a warning \ref{foo}, but this should not~\ref{foo}.

\this should give us errors. $\this should not$. $$\neither should this$$.
\(This is \also legal\). However, \this is not. Errors should also not
be given when the command is ended by a \comma, or likewise. We will also
not react on `silent' commands like this \bf one.

Tries to look after incorrect hyphenation - that one had an incorrect
length -- so had that one.  However, the following ones are correct, even
though we've made 2--3 errors --- easy-peasy, or what? That should indeed
not be written as: ...made 2-3 errors -- easy--peasy, or what?

Furthermore, some uses of abbrevs should be reacted on, i.e. that one. We'll
just making sure that interword spacing is enforced, i.e.\ like that.

Certain types of punctuation may be doubtful, like THIS ONE! That one should
have been written as THIS\@. See?

We'll also check accents. Examples of correct and wrong:
\"{a} \"{b} \"{i} \"{\i} $\hat{i} \tilde{\imath}$


% Of course, `errors' in comments are fully ignored, \like this.
\% \This is thus detected, % \this is not.

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