This function is intended for use with the select_rows_byname
and select_cols_byname
functions.
make_pattern
correctly escapes special characters in row_col_names
,
such as (
and )
, as needed.
Thus, it is highly recommended that make_pattern
be used when
constructing patterns for row and column selections with
select_rows_byname
and select_cols_byname
.
make_pattern( row_col_names, pattern_type = c("exact", "leading", "trailing", "anywhere") )
row_col_names | a vector of row and column names |
---|---|
pattern_type | one of |
an extended regex pattern suitable for use with select_rows_byname
or select_cols_byname
.
pattern_type
controls the type of pattern created:
exact
produces a pattern that selects row or column names by exact match.
leading
produces a pattern that selects row or column names if the item in row_col_names
matches
the beginnings of row or column names.
trailing
produces a pattern that selects row or column names if the item in row_col_names
matches
the ends of row or column names.
anywhere
produces a pattern that selects row or column names if the item in row_col_names
matches
any substring of row or column names.
#> [1] "^a$|^b$"