add array.h/cpp

CMakeLists.txt

@@ -1,9 +1,42 @@
+cmake_minimum_required(VERSION 3.11) # FetchContent
+
 project(keycode)
 
+include(FetchContent)
+include("cmake/Check-from_chars.cmake")
+
+set (LIBS fmt)
+
+if (NOT DEFINED OPTCON_LOCAL_BUILD)
+    FetchContent_Declare(
+        fmt
+        GIT_REPOSITORY https://github.com/fmtlib/fmt
+        GIT_TAG 123913715afeb8a437e6388b4473fcc4753e1c9a # 11.1.4
+    )
+
+    FetchContent_MakeAvailable(fmt)
+endif()
+
+if (NOT FROM_CHARS_WORKS)
+    FetchContent_Declare(
+        fast_float
+        GIT_REPOSITORY https://github.com/fastfloat/fast_float
+        GIT_TAG 77cc847c842c49e7e3477c1e95da2b6540166d66 # 8.0.0
+    )
+
+    FetchContent_MakeAvailable(fast_float)
+
+    list(APPEND LIBS fast_float)
+    add_definitions(-DUSE_FAST_FLOAT)
+endif()
+
 add_library(keycode STATIC
+    src/array.cpp
     src/keycode.c
 )
 
+target_link_libraries(keycode ${LIBS})
+
 target_include_directories(keycode
     PUBLIC src
 )