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.

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.

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.

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.

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.