Quote mark on same line.
rename coll->collection
Clarify splice documentation
rename sub->subcollection
rename con->concatenate
extract vector-concatenate
extract first-section & last-section
whitespace
change comments to assertions
introduce check macro
pass two arguments to check macro
rename check->assert-equal
Make failed tests give useful results
Evaluate expected-value and expression only once
Extract message#
Throw our own AssertionError to remove some garbage