1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
|
# = Synopsis
#
# This library allows command-line tools to encapsulate their usage
# as a comment at the top of the main file. Calling <tt>RDoc::usage</tt>
# then displays some or all of that comment, and optionally exits
# the program with an exit status. We always look for the comment
# in the main program file, so it is safe to call this method
# from anywhere in the executing program.
#
# = Usage
#
# RDoc::usage( [ exit_status ], [ section, ...])
# RDoc::usage_no_exit( [ section, ...])
#
# where:
#
# exit_status::
# the integer exit code (default zero). RDoc::usage will exit
# the calling program with this status.
#
# section::
# an optional list of section names. If specified, only the
# sections with the given names as headings will be output.
# For example, this section is named 'Usage', and the next
# section is named 'Examples'. The section names are case
# insensitive.
#
# = Examples
#
# # Comment block describing usage
# # with (optional) section headings
# # . . .
#
# require 'rdoc/usage'
#
# # Display all usage and exit with a status of 0
#
# RDoc::usage
#
# # Display all usage and exit with a status of 99
#
# RDoc::usage(99)
#
# # Display usage in the 'Summary' section only, then
# # exit with a status of 99
#
# RDoc::usage(99, 'Summary')
#
# # Display information in the Author and Copyright
# # sections, then exit 0.
#
# RDoc::usage('Author', 'Copyright')
#
# # Display information in the Author and Copyright
# # sections, but don't exit
#
# RDoc::usage_no_exit('Author', 'Copyright')
#
# = Author
#
# Dave Thomas, The Pragmatic Programmers, LLC
#
# = Copyright
#
# Copyright (c) 2004 Dave Thomas.
# Licensed under the same terms as Ruby
#
require 'rdoc/markup/simple_markup'
require 'rdoc/markup/simple_markup/to_flow'
require 'rdoc/ri/ri_formatter'
require 'rdoc/ri/ri_options'
module RDoc
# Display usage information from the comment at the top of
# the file. String arguments identify specific sections of the
# comment to display. An optional integer first argument
# specifies the exit status (defaults to 0)
def RDoc.usage(*args)
exit_code = 0
if args.size > 0
status = args[0]
if status.respond_to?(:to_int)
exit_code = status.to_int
args.shift
end
end
# display the usage and exit with the given code
usage_no_exit(*args)
exit(exit_code)
end
# Display usage
def RDoc.usage_no_exit(*args)
main_program_file = caller[-1].sub(/:\d+$/, '')
comment = File.open(main_program_file) do |file|
find_comment(file)
end
comment = comment.gsub(/^\s*#/, '')
markup = SM::SimpleMarkup.new
flow_convertor = SM::ToFlow.new
flow = markup.convert(comment, flow_convertor)
format = "plain"
unless args.empty?
flow = extract_sections(flow, args)
end
options = RI::Options.instance
if args = ENV["RI"]
options.parse(args.split)
end
formatter = options.formatter.new(options, "")
formatter.display_flow(flow)
end
######################################################################
private
# Find the first comment in the file (that isn't a shebang line)
# If the file doesn't start with a comment, report the fact
# and return empty string
def RDoc.gets(file)
if (line = file.gets) && (line =~ /^#!/) # shebang
throw :exit, find_comment(file)
else
line
end
end
def RDoc.find_comment(file)
catch(:exit) do
# skip leading blank lines
0 while (line = gets(file)) && (line =~ /^\s*$/)
comment = []
while line && line =~ /^\s*#/
comment << line
line = gets(file)
end
0 while line && (line = gets(file))
return no_comment if comment.empty?
return comment.join
end
end
#####
# Given an array of flow items and an array of section names, extract those
# sections from the flow which have headings corresponding to
# a section name in the list. Return them in the order
# of names in the +sections+ array.
def RDoc.extract_sections(flow, sections)
result = []
sections.each do |name|
name = name.downcase
copy_upto_level = nil
flow.each do |item|
case item
when SM::Flow::H
if copy_upto_level && item.level >= copy_upto_level
copy_upto_level = nil
else
if item.text.downcase == name
result << item
copy_upto_level = item.level
end
end
else
if copy_upto_level
result << item
end
end
end
end
if result.empty?
puts "Note to developer: requested section(s) [#{sections.join(', ')}] " +
"not found"
result = flow
end
result
end
#####
# Report the fact that no doc comment count be found
def RDoc.no_comment
$stderr.puts "No usage information available for this program"
""
end
end
if $0 == __FILE__
RDoc::usage(*ARGV)
end
|
