Examine the Macro Symbol Table

The symtable function extracts the contents of the macro symbol table and macro function list. The symbol table information is returned as an object. The object can be printed or navigated programatically.

symtable()

Value

An object of class "symtable". The object contains a list of macro symbols and their values. It also contains a list of macro functions, their parameters, and the associated code.

See also

msource()

Other symtable: print.symtable(), symclear(), symget(), symput()

Examples

library(macro)

# Get path to demo macro program
src <- system.file("extdata/Demo4.R", package = "macro")

# Display source code
# - This is the macro input code
cd <- readLines(src)
cat(paste(cd, "\n"))
# #% Create some macro variables
# #%let x <- 1
# #%let y <- 2
# #%let z <- &x + &y
#
# #% Create a macro function
# #%macro test(vl = Hello!)
# print("&vl")
# #%mend

# Execute source code
msource(src, echo = FALSE)

# Examine symbol table
res <- symtable()

# View results
print(res)
# # Macro Symbol Table: 3 macro variables
#   Name Value
# 1   &x     1
# 2   &y     2
# 3   &z 1 + 2
# # Macro Function List: 1 macro functions
#   Name Parameter Default
# 1 test        vl  Hello!

# View results structure
print(res, verbose = TRUE)
# $variables
# $variables$`&x`
# [1] "1"
#
# $variables$`&y`
# [1] "2"
#
# $variables$`&z`
# [1] "1 + 2"
#
#
# $functions
# $functions$test
# $functions$test$parameters
# $functions$test$parameters$vl
# [1] "Hello!"
#
#
# $functions$test$code
# [1] "print(\"&vl\")"
# attr(,"start")
# [1] 8
# attr(,"end")
# [1] 8