%0%                     Default value for empty vectors
dims                    Vector dimensions
list_of                 'list_of' S3 class for homogenous lists
partial_frame           Partially specify columns of a data frame
vec_assert              Assert an argument has known prototype and/or
                        size
vec_bind                Combine many data frames into one data frame
vec_c                   Combine many vectors into one vector
vec_compare             Compare two vectors
vec_count               Count unique values in a vector
vec_data                Extract underlying data
vec_duplicate           Find duplicated values
vec_equal               Test if two vectors are equal
vec_match               Find matching observations across vectors
vec_na                  Create a missing vector
vec_recycle             Vector recycling
vec_size                Number of observations
vec_type                Find the prototype of a set of vectors
vec_unique              Find and count unique values
