read xml file
Usage
read_xml(
xml,
pointer = TRUE,
escapes = FALSE,
declaration = FALSE,
whitespace = TRUE,
empty_tags = FALSE,
skip_control = TRUE
)Arguments
- xml
something to read character string or file
- pointer
should a pointer be returned?
- escapes
bool if characters like "&" should be escaped. The default is no escapes. Assuming that the input already provides valid information.
- declaration
should the declaration be imported
- whitespace
should whitespace pcdata be imported
- empty_tags
should
<b/>or<b></b>be returned- skip_control
should whitespace character be exported
Details
Read xml files or strings to pointer and checks if the input is valid XML. If the input is read into a character object, it will be reevaluated every time it is called. A pointer is evaluated once, but lives only for the lifetime of the R session or once it is gc().
Examples
# a pointer
x <- read_xml("<a><b/></a>")
print(x)
#> <a>
#> <b />
#> </a>
print(x, raw = TRUE)
#> <a><b/></a>
str(x)
#> Class 'pugi_xml' <externalptr>
#> - attr(*, "escapes")= logi FALSE
#> - attr(*, "empty_tags")= logi FALSE
#> - attr(*, "skip_control")= logi TRUE
# a character
y <- read_xml("<a><b/></a>", pointer = FALSE)
print(y)
#> [1] "<a><b/></a>"
print(y, raw = TRUE)
#> [1] "<a><b/></a>"
str(y)
#> chr "<a><b/></a>"
# Errors if the import was unsuccessful
try(z <- read_xml("<a><b/>"))
#> Error : xml import unsuccessful
xml <- '<?xml test="yay" ?><a>A & B</a>'
# difference in escapes
read_xml(xml, escapes = TRUE, pointer = FALSE)
#> [1] "<a>A & B</a>"
read_xml(xml, escapes = FALSE, pointer = FALSE)
#> [1] "<a>A & B</a>"
read_xml(xml, escapes = TRUE)
#> <a>A & B</a>
read_xml(xml, escapes = FALSE)
#> <a>A & B</a>
# read declaration
read_xml(xml, declaration = TRUE)
#> <?xml test="yay"?>
#> <a>A & B</a>