Alternative option mechanism
options is a slight rework on
gives a S3 class
options to the result. This allows the definition
with method for the options. This is useful to execute a
block of code with a set of options.
"with"(data, expr, ...) options(...)
- Options to use. See
- Options to use. This is typically a call to the
- Code to execute.
The result of the expression that is evaulated is modified
in order to keep the option context it is associated with. The class
of the object created by the expression is expanded to
withOptions class and the
attribute that keeps the context in which the object has been created.
This mechanism has been implemented specially for the automatic printing
of objects that happens outside the call to the
function and not reflect the options requested by the user when the object
For the function
with.options, the result of the expression given in
expris returned. See details below.
options function in the base package.
# part of ?glm counts <- c(18,17,15,20,10,20,25,13,12) outcome <- gl(3,1,9) treatment <- gl(3,3) print(d.AD <- data.frame(treatment, outcome, counts)) glm.D93 <- glm(counts ~ outcome + treatment, family=poisson()) summary( glm.D93 ) with( options(show.signif.stars = FALSE,show.coef.Pvalues=FALSE), summary( glm.D93) ) a <- try( with( options( warn = 2) , warning( "more than a warning" ) ), silent = TRUE ) class( a )