Move structures and free procedures back to dedicated files

scripts/build.sh

@@ -9,7 +9,8 @@ if [ ! -e build ]; then mkdir build; else rm build/*; fi
 # Build library
 clang $CFLAGS -Ilib -c lib/parse.c -o build/parse.o
 clang $CFLAGS -Ilib -c lib/desugar.c -o build/desugar.o
-ar -crs build/lib.a build/parse.o build/desugar.o
+clang $CFLAGS -Ilib -c lib/regex.c -o build/regex.o
+ar -crs build/lib.a build/parse.o build/desugar.o build/regex.o
 
 # Build tests
 clang $CFLAGS -Itests -c tests/testing.c -o build/testing.o