Scope modifiers: Difference between revisions
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=={{header|R}}== |
=={{header|R}}== |
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{{incorrect|R|<<- is not a "global assignment" operator. It would also be worth showing R constructs that can emulate dynamic scope, call-by-name, etc.}} |
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R uses lexical scoping – there is a nice introduction to this in the [http://cran.r-project.org/doc/FAQ/R-FAQ.html#Lexical-scoping FAQ on R]. There are no keywords related to scoping, but the [http://stat.ethz.ch/R-manual/R-patched/library/base/html/assign.html assign] function allows you to choose the environment in which a variable is assigned. The global assignment operators , '<<-' and '->>' are effectively shorthand for 'assign(..., envir=globalenv()). |
R uses lexical scoping – there is a nice introduction to this in the [http://cran.r-project.org/doc/FAQ/R-FAQ.html#Lexical-scoping FAQ on R]. There are no keywords related to scoping, but the [http://stat.ethz.ch/R-manual/R-patched/library/base/html/assign.html assign] function allows you to choose the environment in which a variable is assigned. The global assignment operators , '<<-' and '->>' are effectively shorthand for 'assign(..., envir=globalenv()). |
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<lang r>x <- "defined in global env" |
<lang r>x <- "defined in global env" |
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