distill: distill: simple brew wrapper

In R4X: Manipulation of XML structures

Description

distill is a simple wrapper for brew. distill provides functionality to generate brew code from simpler markup closer to the E4X language.

Usage

distill( txt, brew = FALSE, env = sys.frame(sys.parent()) )

Arguments

txt	The text to distill
brew	Is brew called ?
env	Environment where distilling is performed.

Details

distill consist of generating brew ready templates from a different markup that is (arguably) simpler to use in an XML setting. The following table shows the possible transformations from distill code to brew code.

description	distill code	brew code
R code to be cat	{x}	<%=x%>
Loop generator starter	<@i|n>	<%for(i in 1:n){ %>
Loop generator starter	<@i~n>	<%for(i in n){ %>
Loop generator starter	<@i?n>	<%for(i in seq(along = n)){ %>
Loop generator closer	</@>	<%

%>

Value

a character vector ready to be brewed.

Author(s)

Romain Francois <[e-mail]>

References

Jeffrey Horner (2007). brew: Templating Framework for Report Generation.

See Also

xml uses distill to modify the content of XML nodes before parsing. brew

Examples

  y <- "foo"
  txt <- "<test>{x}</test>"
  distill( txt )
  
  cat. <- function(x){
    cat( x, sep = "\n" )
  }
  
  y <- c("foo", "bar")
  txt <- "
    <test>
      <@i~y>
        <foo>{i}</foo>
      </@>
    </test>
    "
  cat.( distill( txt ) )

  txt <- "
    <test>
      <@i|length(y)>
        <foo>{y[i]}</foo>
      </@>
    </test>
    "
  cat.( distill( txt ) )

  txt <- "
    <test>
      <@i?y>
        <foo>{y[i]}</foo>
      </@>
    </test>
    "
  cat.( distill( txt ) )

  

R4X documentation built on May 2, 2019, 4:52 p.m.