This Ruby code defines a CommandModel
class that accepts an array (raw
) and initializes the raw
and len
attributes, with a method write_cmd
to output a command string. The SomeCommand
class inherits from CommandModel
, allowing it to pass the raw
Ruby Code (with Errors):
codeclass CommandModel
attr_reader :raw
attr_reader :len
def initialize(raw)
fail TypeError unless raw.is_a?(Array)
@raw = raw
@len = raw.length
end
def write_cmd
cmd(
"UUT PAYLOAD_WRITE with CCSDS_AP_ID 1, "\
"LENGTH #{@len}, "\
"RAW_BYTES #{@raw}")
end
end
class SomeCommand < CommandModel
def initialize(raw)
super(raw)
end
end
Mycmd = SomeCommand.new([0x01, 0x02, 0x03])
Mycmd.write_cmd()
What’s Wrong with My Code? | Ruby
At first glance, the provided Ruby code defines a CommandModel
class to handle some payload data and a child class SomeCommand
to extend it. However, when running the code, an error is likely to occur because of a missing method and a possible misunderstanding about how certain elements function.
Error: Undefined Method cmd
The method write_cmd
calls cmd
, but the method cmd
is not defined in the code. Ruby will throw a NoMethodError
because it does not know what cmd
refers to. You’ll need to define this method or replace it with a proper output method like puts
if the intent is to print the result.
Error: Naming Conventions
While this isn’t a hard error, Mycmd
does not follow the Ruby naming convention for variables. Variables should be written in snake_case
, so it’s better to name it my_cmd
.
Fix:
- Replace the
cmd
method call withputs
or definecmd
if needed. - Rename
Mycmd
tomy_cmd
for better readability.
Here’s the corrected code:
Corrected Code:
codeclass CommandModel
attr_reader :raw, :len
def initialize(raw)
fail TypeError unless raw.is_a?(Array)
@raw = raw
@len = raw.length
end
def write_cmd
puts(
"UUT PAYLOAD_WRITE with CCSDS_AP_ID 1, "\
"LENGTH #{@len}, "\
"RAW_BYTES #{@raw}"
)
end
end
class SomeCommand < CommandModel
def initialize(raw)
super(raw)
end
end
my_cmd = SomeCommand.new([0x01, 0x02, 0x03])
my_cmd.write_cmd()
Summary:
After these changes, the code will run without issues and correctly output the shape details with the provided input.
The error occurred due to calling an undefined cmd
method. This has been replaced with puts
to print the output.
Following Ruby’s naming convention, Mycmd
has been renamed to my_cmd
to ensure clean and maintainable code.