Automate global variables defintition

[hadley]

• Stick to convention that all SQL functions/values should be in upper case
• Use codetools to find all undefined variables (or maybe just those in sql_expr()?
• Extract all undefined variables that are uppercase

[hadley]

Something like this:

env <- pkgload::load_all()$env
objs <- as.list(env)
funs <- Filter(is.function, objs)

globals <- lapply(funs, codetools::findGlobals)

known <- c(
  names(pkgload::imports_env("dbplyr")),
  names(pkgload::ns_env("dbplyr")),
  names(pkgload::pkg_env("base"))
)
all_globals <- setdiff(unique(unlist(all_globals)), known)

all_globals <- all_globals[all_globals == toupper(all_globals)]

dput(sort(all_globals))