get_param: Create functions to access configuration parameters

In 2DegreesInvesting/r2dii.utils: General Utility Tools

Create functions to access configuration parameters

Description

This is a function factory to create functions which output the value of a configuration parameter.

Usage

get_param(..., if_null = NULL)

Arguments

...	Character string(s) giving a(the) field(s) in a configuration file.
if_null	A value to fill an unset parameter, or the function stop.

Value

A function.

See Also

FINANCIAL.TIMESTAMP

Other functions to get specific 2dii configuration parameters: FINANCIAL.TIMESTAMP()

Examples

# get_param() is a function factory
# Create a `get_a_value()` function
get_a_value <- get_param("a_field")
class(get_a_value)

# Create an example configuration file
config <- glue::glue("
    default:
      a_field: a_value
  ")
show_config(config)

# Write the config file to a temporary file
path_to_config_file <- tempfile()
readr::write_lines(config, path_to_config_file)

# Use `get_a_value()` to get a value from a field in the example config file
get_a_value(file = path_to_config_file)

# Fails: The parameter 'bad' doesn't exist, so it is `NULL`
fails <- get_param("bad", if_null = stop)
try(fails())

returns_null <- get_param("bad")
returns_null()

returns_value_passed_to_if_null <- get_param("bad", if_null = 1)
returns_value_passed_to_if_null()

2DegreesInvesting/r2dii.utils documentation built on March 31, 2022, 11:20 p.m.