### Name: help
### Title: Documentation
### Aliases: help ? topicName .helpForCall .tryHelp
### Keywords: documentation

### ** Examples

help()
help(help)              # the same

help(lapply)
?lapply                 # the same

help("for")             # or ?"for", but the quotes are needed
?"+"

help(package="splines") # get help even when package is not loaded

data()                  # list all available data sets
?women                  # information about data set "women"

topi <- "women"
## Not run: help(topi) ##--> Error: No documentation for 'topi'

try(help("bs", try.all.packages=FALSE)) # reports not found (an error)
help("bs", try.all.packages=TRUE) # reports can be found in package 'splines'

## Not run: 
##D require(methods)
##D ## define a S4 generic function and some methods
##D combo <- function(x, y) c(x, y)
##D setGeneric("combo")
##D setMethod("combo", c("numeric", "numeric"), function(x, y) x+y)
##D 
##D ## assume we have written some documentation for combo, and its methods ....
##D 
##D ?combo  ## produces the function documentation
##D 
##D methods?combo  ## looks for the overall methods documentation
##D 
##D method?combo("numeric", "numeric")  ## documentation for the method above
##D 
##D ?combo(1:10, rnorm(10))  ## ... the same method, selected according to
##D                          ## the arguments (one integer, the other numeric)
##D 
##D ?combo(1:10, letters)    ## documentation for the default method
## End(Not run)