Added lexer, implemented tests build system

makefile

@@ -1,4 +1,63 @@
-export CFLAGS+=-std=c17 -pedantic -Werror
+#directories
+export TOY_SOURCEDIR=source
+export TOY_OUTDIR=out
+export TOY_OBJDIR=obj
 
-all:
+#compiler settings
+CFLAGS+=-std=c17 -pedantic -Werror
+LIBS=-lm
 
+#file names
+TOY_SOURCEFILES=$(wildcard $(TOY_SOURCEDIR)/*.c)
+
+#targets
+all: clean tests
+	@echo no targets ready
+
+.PHONY: tests
+tests:
+	$(MAKE) -C tests
+
+#util targets
+$(TOY_OUTDIR):
+	mkdir $(TOY_OUTDIR)
+
+$(TOY_OBJDIR):
+	mkdir $(TOY_OBJDIR)
+
+$(TOY_OBJDIR)/%.o: $(TOY_SOURCEDIR)/%.c
+	$(CC) -c -o $@ $< $(addprefix -I,$(TOY_SOURCEDIR)) $(CFLAGS)
+
+#util commands
+.PHONY: clean
+clean:
+ifeq ($(shell uname),Linux)
+	find . -type f -name '*.o' -delete
+	find . -type f -name '*.a' -delete
+	find . -type f -name '*.exe' -delete
+	find . -type f -name '*.dll' -delete
+	find . -type f -name '*.lib' -delete
+	find . -type f -name '*.so' -delete
+	find . -type f -name '*.dylib' -delete
+	find . -type d -name 'out' -delete
+	find . -type d -name 'obj' -delete
+else ifeq ($(OS),Windows_NT)
+	del *.o *.a *.exe *.dll *.lib *.so *.dylib
+	del /s out
+	del /s obj
+else ifeq ($(shell uname),Darwin)
+	find . -type f -name '*.o' -delete
+	find . -type f -name '*.a' -delete
+	find . -type f -name '*.exe' -delete
+	find . -type f -name '*.dll' -delete
+	find . -type f -name '*.lib' -delete
+	find . -type f -name '*.so' -delete
+	find . -type f -name '*.dylib' -delete
+	find . -type d -name 'out' -delete
+	find . -type d -name 'obj' -delete
+else
+	@echo "Deletion failed - what platform is this?"
+endif
+
+.PHONY: rebuild
+rebuild: clean all