Function reference • rlang

Tidy evaluation

The programmable data-masking framework developed for the tidyverse.

Tools

embrace-operator curly-curly: Embrace operator {{

glue-operators: Name injection with "{" and "{{"

dot-data .data tidyeval-data .env: .data and .env pronouns

Metaprogramming tools

injection-operator bang-bang !!: Injection operator !!

splice-operator !!!: Splice operator !!!

qq_show: Show injected expression

englue(): Defuse function arguments with glue

expr: Defuse an R expression

enquo() enquos(): Defuse function arguments

sym() syms() data_sym() data_syms(): Create a symbol or list of symbols

as_label(): Create a default name for an R object

as_name(): Extract names from symbols

Advanced tools

enexpr() exprs() enexprs() ensym() ensyms() quo() quos() enquo0() enquos0(): Advanced defusal operators

eval_tidy(): Evaluate an expression with quosures and pronoun support

as_data_mask() as_data_pronoun() new_data_mask(): Create a data mask

Function arguments

Check arguments

arg_match() arg_match0(): Match an argument to a character vector

check_exclusive(): Check that arguments are mutually exclusive

check_required(): Check that argument is supplied

missing_arg() is_missing() maybe_missing(): Generate or handle a missing argument

Check dots

check_dots_empty(): Check that dots are empty

check_dots_used(): Check that all dots have been used

check_dots_unnamed(): Check that all dots are unnamed

Collect dynamic dots

Collect arguments contained in ... with !!! and name-injection support.

dyn-dots tidy-dots doc_dots_dynamic :=: Dynamic dots features

list2() dots_list(): Collect dynamic dots in a list

pairlist2(): Collect dynamic dots in a pairlist

splice() is_spliced() is_spliced_bare(): Splice values at dots collection time

Error handling

Signal errors and other conditions

abort() warn() inform() signal() reset_warning_verbosity() reset_message_verbosity(): Signal an error, warning, or message

cnd_signal(): Signal a condition object

local_use_cli(): Use cli to format error messages

Handle errors

global_handle(): Register default global handlers

global_entrace(): Entrace unexpected errors

global_prompt_install(): Prompt user to install missing packages

try_fetch(): Try an expression with condition handlers

caller_arg: Find the caller argument for error messages

local_error_call(): Set local error call in an execution environment

args_error_context: Documentation anchor for error arguments

catch_cnd(): Catch a condition

Backtraces

last_error() last_trace(): Last abort() error

last_warnings() last_messages(): Display last messages and warnings

global_entrace(): Entrace unexpected errors

rlang_backtrace_on_error add_backtrace rlang_backtrace_on_error_report rlang_backtrace_on_warning_report: Display backtrace on error

trace_back() trace_length(): Capture a backtrace

Conditions

rlang_error: Errors of class rlang_error

cnd_message() cnd_header() cnd_body() cnd_footer(): Build an error message from parts

format_error_bullets(): Format bullets for error messages

cnd_inherits(): Does a condition or its ancestors inherit from a class?

Session

State

is_installed() check_installed(): Are packages installed in any of the libraries?

is_interactive() local_interactive() with_interactive(): Is R running interactively?

local_options() with_options() push_options() peek_options() peek_option(): Change global options

on_load() run_on_load() on_package_load(): Run expressions on load

faq-options: Global options for rlang

Search path and namespaces

search_envs() search_env() pkg_env() pkg_env_name() is_attached() base_env() global_env(): Search path environments

empty_env(): Get the empty environment

is_namespace(): Is an object a namespace environment?

ns_env() ns_imports_env() ns_env_name(): Get the namespace of a package

env_name() env_label(): Label of an environment

Defused expressions

parse_expr() parse_exprs() parse_quo() parse_quos(): Parse R code

expr_print() expr_deparse(): Print an expression

is_expression() is_syntactic_literal() is_symbolic(): Is an object an expression?

exprs_auto_name() quos_auto_name(): Ensure that all elements of a list of expressions are named

Evaluate

eval_tidy(): Evaluate an expression with quosures and pronoun support

eval_bare(): Evaluate an expression in an environment

exec(): Execute a function

inject(): Inject objects in an R expression

Symbols

sym() syms() data_sym() data_syms(): Create a symbol or list of symbols

is_symbol(): Is object a symbol?

as_string(): Cast symbol to string

Calls

call2(): Create a call

is_call(): Is object a call?

call_args() call_args_names(): Extract arguments from a call

call_inspect(): Inspect a call

call_match(): Match supplied arguments to function definition

call_modify(): Modify the arguments of a call

call_name() call_ns() is_call_simple(): Extract function name or namespace of a call

Quosures

new_quosure() as_quosure() is_quosure(): Create a quosure from components

new_quosures() as_quosures() is_quosures(): Create a list of quosures

quo_is_missing() quo_is_symbol() quo_is_call() quo_is_symbolic() quo_is_null() quo_get_expr() quo_get_env() quo_set_expr() quo_set_env(): Quosure getters, setters and predicates

quo_squash(): Squash a quosure

Formulas

f_rhs() `f_rhs<-`() f_lhs() `f_lhs<-`() f_env() `f_env<-`(): Get or set formula components

f_text() f_name() f_label(): Turn RHS of formula into a string or label

new_formula(): Create a formula

is_formula() is_bare_formula(): Is object a formula?

Objects

hash() hash_file(): Hashing

Environments

env() new_environment(): Create a new environment

env_print(): Pretty-print an environment

env_parent() env_tail() env_parents(): Get parent environments

env_depth(): Depth of an environment chain

get_env() set_env() env_poke_parent(): Get or set the environment of an object

env_clone() env_coalesce(): Clone or coalesce an environment

env_inherits(): Does environment inherit from another environment?

is_environment() is_bare_environment(): Is object an environment?

as_environment(): Coerce to an environment

current_call() current_fn() current_env() caller_call() caller_fn() caller_env() frame_call() frame_fn(): Get properties of the current or caller frame

env_browse() env_is_browsed(): Browse environments

env_is_user_facing(): Is frame environment user facing?

Stack

current_call() current_fn() current_env() caller_call() caller_fn() caller_env() frame_call() frame_fn(): Get properties of the current or caller frame

Environment bindings

env_bind() env_bind_lazy() env_bind_active() `%<~%`: Bind symbols to objects in an environment

env_unbind(): Remove bindings from an environment

env_poke(): Poke an object in an environment

env_cache(): Cache a value in an environment

local_bindings() with_bindings(): Temporarily change bindings of an environment

env_has(): Does an environment have or see bindings?

env_get() env_get_list(): Get an object in an environment

env_names() env_length(): Names and numbers of symbols bound in an environment

Functions

new_function(): Create a function

as_function() is_lambda(): Convert to function

is_function() is_closure() is_primitive() is_primitive_eager() is_primitive_lazy(): Is object a function?

fn_fmls() fn_fmls_names() fn_fmls_syms() `fn_fmls<-`() `fn_fmls_names<-`(): Extract arguments from a function

fn_body() `fn_body<-`(): Get or set function body

fn_env() `fn_env<-`(): Return the closure environment of a function

as_closure(): Transform to a closure

S3

inherits_any() inherits_all() inherits_only(): Does an object inherit from a set of classes?

zap() is_zap(): Create zap objects

as_bytes() parse_bytes(): Human readable memory sizes

new_box() is_box() unbox(): Box a value

as_box() as_box_if(): Convert object to a box

done() is_done_box(): Box a final value for early termination

Attributes

set_names(): Set names of a vector

names2() `names2<-`(): Get names of a vector

has_name(): Does an object have an element with this name?

is_named() is_named2() have_name(): Is object named?

zap_srcref(): Zap source references

Vectors

lgl() int() dbl() cpl() chr() bytes(): Create vectors

list2() dots_list(): Collect dynamic dots in a list

rep_along() rep_named(): Create vectors matching the length of a given vector

seq2() seq2_along(): Increasing sequence of integers in an interval

Type predicates

is_list() is_atomic() is_vector() is_integer() is_double() is_complex() is_character() is_logical() is_raw() is_bytes() is_null(): Type predicates

is_scalar_list() is_scalar_atomic() is_scalar_vector() is_scalar_integer() is_scalar_double() is_scalar_complex() is_scalar_character() is_scalar_logical() is_scalar_raw() is_string() is_scalar_bytes() is_bool(): Scalar type predicates

is_bare_list() is_bare_atomic() is_bare_vector() is_bare_double() is_bare_complex() is_bare_integer() is_bare_numeric() is_bare_character() is_bare_logical() is_bare_raw() is_bare_string() is_bare_bytes(): Bare type predicates

is_empty(): Is object an empty vector or NULL?

is_integerish() is_bare_integerish() is_scalar_integerish(): Is a vector integer-like?

is_true() is_false(): Is object identical to TRUE or FALSE?

Weak references

is_weakref(): Is object a weak reference?

new_weakref(): Create a weak reference

wref_key() wref_value(): Get key/value from a weak reference object

Operators

`%||%`: Default value for NULL

`%|%`: Replace missing values

`%@%` `%@%<-`(): Infix attribute accessor and setter