Single-bracket access on a catt_df object

Intercepts column selection by the pre-1.11.0 Title-Case names and stops with a migration message. The check fires when an old name appears in the column-selector position: j for the df[i, j] two-index form, or i for the df[j] one-index column-selection form. Row-only access (df[i, ]) and access by new column names fall through to the data.frame method via NextMethod().

Usage

# S3 method for class 'catt_df'
x[i, j, ...]

Arguments

x

A catt_df object.

i, j

Row / column selectors; see [.data.frame.

...

Further arguments passed through.

Value

The selected subset, as for [.data.frame.