feat(build): add Makefile for libraries

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

library/Makefile.common

@@ -0,0 +1,25 @@
+TOP := $(dir $(lastword $(MAKEFILE_LIST)))
+EXTRACT_DEPS = $(TOP)/extract_deps
+LEAN_FILES = $(wildcard *.lean)
+OLEAN_FILES = $(LEAN_FILES:.lean=.olean)
+DEPS = make.deps
+
+all: $(OLEAN_FILES) $(DEPS)
+
+%.olean: %.lean
+	$(LEAN) $< -o $@
+
+%.olean: %.lua
+	$(LEAN) $< -o $@
+
+.PHONY: all clean
+
+clean:
+	-rm -f *.olean $(DEPS)
+
+$(DEPS): $(LEAN_FILES)
+	LEAN=$(LEAN) $(EXTRACT_DEPS) $(LEAN_FILES) > make.deps
+
+ifneq ($(MAKECMDGOALS),clean)
+-include $(DEPS)
+endif

library/extract_deps

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+for LEANFILE in $@; do
+    OLEANFILE=${LEANFILE//.lean/.olean}
+    DEPS=`$LEAN --deps $LEANFILE | cut -d ' ' -f 2- | tr "\n" " "`
+    echo -n "$OLEANFILE:"
+    for DEP in $DEPS; do
+        echo -n " ${DEP}"
+    done
+    echo ""
+done

library/standard/Makefile

@@ -0,0 +1 @@
+include ../Makefile.common

src/CMakeLists.txt

@@ -270,3 +270,10 @@ file(GLOB_RECURSE LEAN_SOURCES
          ${LEAN_SOURCE_DIR}/[A-Za-z]*.h)
 add_style_check_target(style "${LEAN_SOURCES}")
 add_test(NAME style_check COMMAND ${LEAN_SOURCE_DIR}/cmake/Modules/cpplint.py ${LEAN_SOURCES})
+
+add_custom_target(
+   standard_lib ALL
+   COMMAND make LEAN=${CMAKE_BINARY_DIR}/shell/lean
+   DEPENDS ${CMAKE_BINARY_DIR}/shell/lean
+   WORKING_DIRECTORY ${LEAN_SOURCE_DIR}/../library/standard
+)