mirror of
https://github.com/EiffelSoftware/eiffel-org.git
synced 2025-12-06 14:52:03 +01:00
2839895650
git-svn-id: https://svn.eiffel.com/eiffel-org/trunk@2328 abb3cda0-5349-4a8f-a601-0c33ac3a8c38
69 lines
2.6 KiB
Plaintext
69 lines
2.6 KiB
Plaintext
[[Property:modification_date|Thu, 22 Nov 2018 19:50:45 GMT]]
|
|
[[Property:publication_date|Thu, 22 Nov 2018 19:50:45 GMT]]
|
|
[[Property:title|Example: Command line arguments]]
|
|
[[Property:weight|0]]
|
|
[[Property:uuid|ba852d83-3c02-4d38-088a-60b76fe5c63f]]
|
|
==Description==
|
|
|
|
Retrieve the list of command-line arguments given to the program.
|
|
Example command line:
|
|
<code lang="text">
|
|
myprogram -c "alpha beta" -h "gamma"
|
|
</code>
|
|
|
|
==Notes==
|
|
|
|
This class inherits functionality for dealing with command line arguments from class <code lang="eiffel">ARGUMENTS</code>. It uses the feature <code lang="eiffel">separate_character_option_value</code> to return the values by option name for each of the two arguments. <code lang="eiffel">ARGUMENTS</code> provides a rich set of features for command line argument processing.
|
|
|
|
The simple version in [[#Solution|Solution]] below is as submitted to Rosetta Code to illustrate class <code lang="eiffel">ARGUMENTS</code>, but it should be noted that <code lang="eiffel">separate_character_option_value</code> is of a detached type and will return a void reference if no value is found for a specified character option. Therefore, a safer version of the use of <code lang="eiffel">separate_character_option_value</code> would include object test on the result:
|
|
|
|
<code>
|
|
if attached separate_character_option_value ('c') as l_val then
|
|
print ("Command line argument value for option 'c' is: ")
|
|
print (l_val + "%N")
|
|
end
|
|
if attached separate_character_option_value ('h') as l_val then
|
|
print ("Command line argument value for option 'h' is: ")
|
|
print (l_val + "%N")
|
|
end
|
|
</code>
|
|
|
|
==Source==
|
|
|
|
Problem description from [http://rosettacode.org/wiki/Command-line_arguments Rosetta Code]
|
|
|
|
==Solution==
|
|
|
|
<code>
|
|
class
|
|
APPLICATION
|
|
inherit
|
|
ARGUMENTS
|
|
create
|
|
make
|
|
feature {NONE} -- Initialization
|
|
make
|
|
-- Print values for arguments with options 'c' and 'h'.
|
|
do
|
|
print ("Command line argument value for option 'c' is: ")
|
|
print (separate_character_option_value ('c') + "%N")
|
|
print ("Command line argument value for option 'h' is: ")
|
|
print (separate_character_option_value ('h') + "%N")
|
|
io.read_line -- Keep console window open
|
|
end
|
|
end
|
|
</code>
|
|
|
|
|
|
==Output (for command line arguments: -c "alpha beta" -h "gamma")==
|
|
|
|
<code lang="text">
|
|
Command line argument value for option 'c' is: alpha beta
|
|
Command line argument value for option 'h' is: gamma
|
|
</code>
|
|
|
|
|
|
{{SeeAlso|[[Execution_profiles|How to run with arguments]]}}
|
|
|
|
|