What is the difference between parent.frame() and parent.env() in R; how do they differ in call by reference?

What is the difference between parent.frame() and parent.env() in R; how do they differ in call by reference?

r environment function-call stack-frame

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Assign multiple objects to .GlobalEnv from within a function

r global environment assign assignment-operator

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create a formula in a data.table environment in R

r environment data.table

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R: how do you merge/combine two environments?

r environment

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Assignment to replace value in nonlocal list

r list environment assign

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What is the difference between with and within in R?

r environment

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How do we set constant variables while building R packages?

r global-variables environment-variables packages environment

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How are environments, (en)closures, and frames related?

r function closures frame environment

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Scoping and functions in R 2.11.1 : What's going wrong?

r function environment scoping

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How to create a constant inside R package?

r package constants environment

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Remove objects in .GlobalEnv from within a function

r environment

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Behavior of saveRDS() and readRDS() in regard to objects' attributes

r persistence environment persistent rdata

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update() inside a function only searches the global environment?

r function environment

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how to compare environment for equality in R

r frame environment

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R how to restrict the names that are in scope to those I create explicitly?

r scope environment

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