split internal modules

res/modules/internal/extensions/file.lua

@@ -0,0 +1,45 @@
+function file.name(path)
+    return path:match("([^:/\\]+)$")
+end
+
+function file.stem(path)
+    local name = file.name(path)
+    return name:match("(.+)%.[^%.]+$") or name
+end
+
+function file.ext(path)
+    return path:match("%.([^:/\\]+)$")
+end
+
+function file.prefix(path)
+    return path:match("^([^:]+)")
+end
+
+function file.parent(path)
+    local dir = path:match("(.*)/")
+    if not dir then
+        return file.prefix(path)..":"
+    end
+    return dir
+end
+
+function file.path(path)
+    local pos = path:find(':')
+    return path:sub(pos + 1)
+end
+
+function file.join(a, b)
+    if a[#a] == ':' then
+        return a .. b
+    end
+    return a .. "/" .. b
+end
+
+function file.readlines(path)
+    local str = file.read(path)
+    local lines = {}
+    for s in str:gmatch("[^\r\n]+") do
+        table.insert(lines, s)
+    end
+    return lines
+end