# lifecycle 0.1.0.9000 Unreleased

• New is_present() function to test whether the caller has supplied a deprecated() function.

# lifecycle 0.1.0 2019-08-01

• Deprecated functions under the control of the developer now warn repeatedly in unit tests.

• Deprecation warnings now record a backtrace. Call lifecycle::last_warnings() and lifecycle::last_warning() to print the warnings that occurred during the last command, along with their backtraces.

• The naming scheme of signaller functions has been simplified:

• signal_soft_deprecated() is now deprecate_soft().
• warn_deprecated() is now deprecate_warn().
• stop_defunct() is now deprecate_stop().
• The signaller functions now take a version and two descriptors for the deprecated feature and its replacement (the latter is optional). The deprecation message is built from these components. You can pass a details argument to append additional information to the generated deprecation message.

• Helpers from rlang’s compat-lifecycle.R drop-in file are now exported in this package.