has_ctl
checks for any Control Sequence, whereas has_sgr
checks only
for ANSI CSI SGR sequences. You can check for different types of sequences
with the ctl
parameter.
has_ctl(x, ctl = "all", warn = getOption("fansi.warn"), which)has_sgr(x, warn = getOption("fansi.warn"))
a character vector or object that can be coerced to character.
character, which Control Sequences should be treated specially. See the "_ctl vs. _sgr" section for details.
"nl": newlines.
"c0": all other "C0" control characters (i.e. 0x01-0x1f, 0x7F), except for newlines and the actual ESC (0x1B) character.
"sgr": ANSI CSI SGR sequences.
"csi": all non-SGR ANSI CSI sequences.
"esc": all other escape sequences.
"all": all of the above, except when used in combination with any of the above, in which case it means "all but".
TRUE (default) or FALSE, whether to warn when potentially
problematic Control Sequences are encountered. These could cause the
assumptions fansi
makes about how strings are rendered on your display
to be incorrect, for example by moving the cursor (see fansi).
character, deprecated in favor of ctl
.
logical of same length as x
; NA values in x
result in NA values
in return
The *_ctl
versions of the functions treat all Control Sequences specially
by default. Special treatment is context dependent, and may include
detecting them and/or computing their display/character width as zero. For
the SGR subset of the ANSI CSI sequences, fansi
will also parse, interpret,
and reapply the text styles they encode if needed. You can modify whether a
Control Sequence is treated specially with the ctl
parameter. You can
exclude a type of Control Sequence from special treatment by combining
"all" with that type of sequence (e.g. ctl=c("all", "nl")
for special
treatment of all Control Sequences but newlines). The *_sgr
versions
only treat ANSI CSI SGR sequences specially, and are equivalent to the
*_ctl
versions with the ctl
parameter set to "sgr".
fansi for details on how Control Sequences are interpreted, particularly if you are getting unexpected results.
# NOT RUN {
has_ctl("hello world")
has_ctl("hello\nworld")
has_ctl("hello\nworld", "sgr")
has_ctl("hello\033[31mworld\033[m", "sgr")
has_sgr("hello\033[31mworld\033[m")
has_sgr("hello\nworld")
# }
Run the code above in your browser using DataLab