-- {{{ File operations
--- see if the file exists and is readable
-function helpers.file_exists(file)
- local f = io.open(file)
- if f then
- local s = f:read()
- f:close()
- f = s
- end
- return f ~= nil
-end
-
--- get all lines from a file, returns an empty
--- list/table if the file does not exist
-function helpers.lines_from(file)
- if not helpers.file_exists(file) then return {} end
- local lines = {}
- for line in io.lines(file) do
- lines[#lines + 1] = line
- end
- return lines
-end
-
--- match all lines from a file, returns an empty
--- list/table if the file or match does not exist
-function helpers.lines_match(regexp, file)
- local lines = {}
- for index,line in pairs(helpers.lines_from(file)) do
- if string.match(line, regexp) then
- lines[index] = line
- end
- end
- return lines
-end
-
--- get first line of a file, return nil if
--- the file does not exist
-function helpers.first_line(file)
- return helpers.lines_from(file)[1]
-end
-
--- get first non empty line from a file,
--- returns nil otherwise
-function helpers.first_nonempty_line(file)
- for k,v in pairs(helpers.lines_from(file)) do
- if #v then return v end
- end
- return nil
+-- check if the file exists and is readable
+function helpers.file_exists(path)
+ local file = io.open(path, "rb")
+ if file then file:close() end
+ return file ~= nil
+end
+
+-- get a table with all lines from a file
+function helpers.lines_from(path)
+ local lines = {}
+ for line in io.lines(path) do
+ lines[#lines + 1] = line
+ end
+ return lines
+end
+
+-- get a table with all lines from a file matching regexp
+function helpers.lines_match(regexp, path)
+ local lines = {}
+ for line in io.lines(path) do
+ if string.match(line, regexp) then
+ lines[#lines + 1] = line
+ end
+ end
+ return lines
+end
+
+-- get first line of a file
+function helpers.first_line(path)
+ local file, first = io.open(path, "rb"), nil
+ if file then
+ first = file:read("*l")
+ file:close()
+ end
+ return first
+end
+
+-- get first non empty line from a file
+function helpers.first_nonempty_line(path)
+ for line in io.lines(path) do
+ if #line then return line end
+ end
+ return nil
end
-- }}}