diff --git a/spec/actions_spec.lua b/spec/actions_spec.lua
index b927417..f5a37fb 100644
--- a/spec/actions_spec.lua
+++ b/spec/actions_spec.lua
@@ -183,7 +183,7 @@ describe("actions", function()
 
    it("for commands are called in reverse order", function()
       local args = {}
-      
+
       local parser = Parser():action(function(passed_args)
          args[1] = passed_args
          args.last = 1
diff --git a/spec/help_spec.lua b/spec/help_spec.lua
index d167fcb..840a287 100644
--- a/spec/help_spec.lua
+++ b/spec/help_spec.lua
@@ -51,7 +51,7 @@ An epilog.]], parser:get_help())
          :args "2"
       parser:argument "maybe-fourth"
          :args "?"
-      parser:argument("others", "Optional. ")
+      parser:argument("others", "Optional.")
          :args "*"
 
       assert.equal([[
@@ -62,7 +62,7 @@ Arguments:
    first
    second-and-third
    maybe-fourth
-   others                Optional. 
+   others                Optional.
 
 Options:
    -h, --help            Show this help message and exit.]], parser:get_help())
@@ -92,17 +92,17 @@ Options:
          :count "0-2"
          :target "verbosity"
          :description [[
-Sets verbosity level. 
--v: Report all warnings. 
--vv: Report all debugging information. ]]
+Sets verbosity level.
+-v: Report all warnings.
+-vv: Report all debugging information.]]
 
       assert.equal([[
 Usage: foo [-v] [-h]
 
 Options:
-   -v                    Sets verbosity level. 
-                         -v: Report all warnings. 
-                         -vv: Report all debugging information. 
+   -v                    Sets verbosity level.
+                         -v: Report all warnings.
+                         -vv: Report all debugging information.
    -h, --help            Show this help message and exit.]], parser:get_help())
    end)
 
@@ -131,14 +131,14 @@ Options:
       parser:option "-p"
          :default "8080"
          :show_default(false)
-         :description "Port. "
+         :description "Port."
 
       assert.equal([[
 Usage: foo [-o <o>] [-p <p>] [-h]
 
 Options:
    -o <o>
-   -p <p>                Port. 
+   -p <p>                Port.
    -h, --help            Show this help message and exit.]], parser:get_help())
    end)
 
diff --git a/spec/integrity_spec.lua b/spec/integrity_spec.lua
index 1817074..7aeea39 100644
--- a/spec/integrity_spec.lua
+++ b/spec/integrity_spec.lua
@@ -81,17 +81,17 @@ Did you mean '--from'?
          assert.equal([[
 Usage: ]]..script..[[ [-v] [-h] <input> [<command>] ...
 
-A testing program. 
+A testing program.
 
 Arguments:
    input
 
 Options:
-   -v, --verbose         Sets verbosity level. 
+   -v, --verbose         Sets verbosity level.
    -h, --help            Show this help message and exit.
 
 Commands:
-   install               Install a rock. 
+   install               Install a rock.
 ]], get_output("--help"))
       end)
 
@@ -99,15 +99,15 @@ Commands:
          assert.equal([[
 Usage: ]]..script..[[ install [-f <from>] [-h] <rock> [<version>]
 
-Install a rock. 
+Install a rock.
 
 Arguments:
-   rock                  Name of the rock. 
-   version               Version of the rock. 
+   rock                  Name of the rock.
+   version               Version of the rock.
 
 Options:
    -f <from>, --from <from>
-                         Fetch the rock from this server. 
+                         Fetch the rock from this server.
    -h, --help            Show this help message and exit.
 ]], get_output("foo install --help"))
       end)
diff --git a/spec/script.lua b/spec/script.lua
index ea666c9..5690d3e 100755
--- a/spec/script.lua
+++ b/spec/script.lua
@@ -2,28 +2,28 @@
 local Parser = require "argparse"
 
 local parser = Parser()
-   :description "A testing program. "
+   :description "A testing program."
    :require_command(false)
 
 parser:argument "input"
 
 parser:flag "-v" "--verbose"
-   :description "Sets verbosity level. "
+   :description "Sets verbosity level."
    :target "verbosity"
    :count "0-2"
 
 local install = parser:command "install"
-   :description "Install a rock. "
+   :description "Install a rock."
 
 install:argument "rock"
-   :description "Name of the rock. "
+   :description "Name of the rock."
 
 install:argument "version"
-   :description "Version of the rock. "
+   :description "Version of the rock."
    :args "?"
 
 install:option "-f" "--from"
-   :description "Fetch the rock from this server. "
+   :description "Fetch the rock from this server."
    :target "server"
 
 parser:get_usage()
diff --git a/src/argparse.lua b/src/argparse.lua
index de44b2a..53ef173 100644
--- a/src/argparse.lua
+++ b/src/argparse.lua
@@ -48,7 +48,7 @@ local function class(prototype, properties, parent)
    if properties then
       local names = {}
 
-      -- Create setter methods and fill set of property names. 
+      -- Create setter methods and fill set of property names.
       for _, property in ipairs(properties) do
          local name, callback = property[1], property[2]
 
@@ -422,7 +422,7 @@ function Argument:_get_action()
    return action, init
 end
 
--- Returns placeholder for `narg`-th argument. 
+-- Returns placeholder for `narg`-th argument.
 function Argument:_get_argname(narg)
    local argname = self._argname or self:_get_default_argname()
 
@@ -441,7 +441,7 @@ function Option:_get_default_argname()
    return "<" .. self:_get_default_target() .. ">"
 end
 
--- Returns label to be shown in the help message. 
+-- Returns label to be shown in the help message.
 function Argument:_get_label()
    return self._name
 end
@@ -687,7 +687,7 @@ function Parser:get_help()
    end
 
    local blocks = {self:get_usage()}
-   
+
    if self._description then
       table.insert(blocks, self._description)
    end