diagnostics.md

Index

BTC::Diagnostics

Diagnostics provides extensive details of inner workings of various algorithms. For instance, when script is parsed and detects non-canonical encoding of certain elements, it is not an error condition, but an unusual case that can be important for debugging.

You can wrap any piece of code in Diagnostics.current.record { ... } to collect all diagnostic messages or use Diagnostics.current.trace { ... } to output all the messages to STDERR.

Class Method

current

An instance of BTC::Diagnostics unique to the current thread.

Instance Methods

last_message

Returns the latest recorded message. See add_message.

last_info

Returns the latest recorded info object associated with the latest message. See add_message.

last_item

Returns the Diagnostics::Item object that contains latest message and info.

add_message(message, info: nil)

Records a message (String) with an optional info object.

When executed within a trace {...} block, message is written to STDERR or another stream specified in trace.

When executed within a record {...} block, an Item containing both message and info is added to an array returned from record.

record { ... }

Returns an array of all Item instances recorded by add_message within the block.

Diagnostics.current.record do
  Diagnostics.current.add_message("Hello")
  Diagnostics.current.add_message("world")
end.map(&:to_s)

["Hello", "world"]

trace(stream = $stderr) { ... }

Writes every recorded message to a given stream. Default stream is $stderr.

Diagnostics.current.trace do
  Diagnostics.current.add_message("Hello")
  Diagnostics.current.add_message("world")
end

Hello
world

Diagnostics::Item

Item class represents a pair of message (String) and an arbitrary info object.

message

Message string.

info

Additional object of arbitrary type. Default value is nil.

to_s

Returns message.