swirl (version 2.4.1)

expr_creates_var: Test that a new variable has been created.

Description

Tests if the e$expr creates one new variable (of correct name if given.) If so, returns TRUE.

Usage

expr_creates_var(correctName = NULL)

Arguments

correctName

expected name of the new variable or NULL

Value

• TRUE or FALSE

See Also

Other AnswerTests: AnswerTests, any_of_exprs, calculates_same_value, expr_identical_to, expr_is_a, expr_uses_func, func_of_newvar_equals, omnitest, val_has_length, val_matches, var_is_a

Examples

# Test if the user has entered an expression which creates
# a new variable of any name.
expr_creates_var()
#
# Test if the user has entered an expression which creates
# a variable named 'myNum'
#
expr_creates_var('myNum')