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Find the section related to your variable type or use case, run through the checklist to help you think about what state your variable should be in, then add some assertions to your code.
is_numeric, is_character,
is_data.frame, coerce_to, etc.)is_scalar, is_empty, is_non_empty,
use_first, has_dims, DIM, etc.)is_na, is_not_na)NULL allowed? (is_null, is_not_null)has_duplicates, has_no_duplicates)has_any_attributes)is_finite, is_infinite,
is_nan, is_not_nan, etc.).is_in_range, is_positive, is_percentage, etc.)is_complex, is_real, is_imaginary)is_whole_number, is_integer)is_divisible_by, is_even,
is_odd)is_empty_character,
is_missing_or_empty_character, is_not_missing_nor_empty_character)is_factor, and base::factor)is_email_address,
is_credit_card_number, is_uk_postcode, is_us_zip_code, and many more)is_valid_variable_name,
is_valid_r_code)is_existing_file,
is_dir)is_readable_file, is_writable_file, is_executable_file)is_readable_connection,
is_writable_connection)is_windows, is_linux, is_mac,
is_solaris, is_unix)standardize_path in
pathological, in_dir in
devtools)PATH environment variable have an effect? (is_on_os_path)r_has_png_capability,
r_has_jpeg_capability, r_has_tiff_capability)Any scripts or data that you put into this service are public.
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