This is pdfTeX, Version 3.14159265-2.6-1.40.17 (TeX Live 2016) (preloaded format=pdflatex 2017.3.20)  24 MAR 2017 11:04
entering extended mode
 restricted \write18 enabled.
 file:line:error style messages enabled.
 %&-line parsing enabled.
**hal_prefs.tex
(./hal_prefs.tex
LaTeX2e <2016/03/31>
Babel <3.9r> and hyphenation patterns for 83 language(s) loaded.

./hal_prefs.tex:3: LaTeX Error: \usepackage before \documentclass.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...                                              
                                                  
l.3 \usepackage{
                beamerthemesplit}
? 
./hal_prefs.tex:3: Emergency stop.
 ...                                              
                                                  
l.3 \usepackage{
                beamerthemesplit}
\usepackage may only appear in the document preamble, i.e.,
between \documentclass and \begin{document}.

 
Here is how much of TeX's memory you used:
 6 strings out of 493014
 277 string characters out of 6133351
 53601 words of memory out of 5000000
 3648 multiletter control sequences out of 15000+600000
 3640 words of font info for 14 fonts, out of 8000000 for 9000
 1141 hyphenation exceptions out of 8191
 5i,0n,5p,45b,14s stack positions out of 5000i,500n,10000p,200000b,80000s
./hal_prefs.tex:3:  ==> Fatal error occurred, no output PDF file produced!