# dataframe_merge_impl

A dataframe whose value is the merge of two dataframes, in the sense of the “merge” command of “R”. The merge will be re-run as needed to reflect changes in the source dataframes; evaluation is lazy.

# set_x

    some_dfm set_x x_dataframe

Indicate that the x argument of the R “merge” command should be `eN["x_dataframe"]`. The x component of the suffixes argument will be `x_dataframe`.

# set_y

    some_dfm set_y y_dataframe

Indicate that the y argument of the R “merge” command should be `eN["y_dataframe"]`. The y component of the suffixes argument will be `y_dataframe`.

# set_x_key

    some_dfn set_x_key key_col...

Indicate that the by.x argument of the R “merge” command should be `key_col`. If this is a single column, the quotation marks are required, and if this is a multiple column constraint, the c() is necessary.

# set_y_key

    some_dfn set_y_key key_col...

Indicate that the by.y argument of the R “merge” command should be `key_col`. If this is a single column, the quotation marks are required, and if this is a multiple column constraint, the c() is necessary.