Access question values from survey responses

This function provides a functional interface to access question values from the all_data reactive values list. It is equivalent to using all_data$question_id but allows programmatic access using a string variable or unquoted name. Multiple question IDs can be provided to retrieve multiple values at once.

Usage

sd_values(..., as_numeric = NULL, as_vector = NULL)

Arguments

...

One or more question IDs to retrieve. Each can be provided as an unquoted name (e.g., age) or a quoted string (e.g., "age").

as_numeric

Logical or NULL. Controls numeric type conversion:

Value	Behavior
`NULL` (default)	Auto-detect: checks if value looks numeric, converts if so. Non-numeric values stay as character.
`TRUE`	Force convert: always calls `as.numeric()`. Non-convertible values become `NA`.
`FALSE`	Never convert: returns value as-is, no detection.

as_vector

Logical or NULL. Controls splitting of pipe-separated values:

Value	Behavior
`NULL` (default)	Auto-detect: checks if pipe symbol exists, splits if found.
`TRUE`	Force split: always splits on pipe.
`FALSE`	Never split: returns value as-is, no detection.

Value

If a single question ID is provided, returns the value of that question. If multiple question IDs are provided, returns an unnamed vector of values. Returns NULL for any question ID that doesn't exist.

Examples

if (FALSE) { # \dontrun{
  library(surveydown)

  server <- function(input, output, session) {
    # Single value access - all equivalent:
    age1 <- all_data$age
    age2 <- sd_values(age)        # Unquoted (recommended)
    age3 <- sd_values("age")      # Quoted (also works)

    # Multiple values at once:
    values <- sd_values(age, name, country)
    # Returns values with auto-detection (numeric converted, pipes split)

    # Default behavior (NULL) auto-detects and converts numeric values:
    age <- sd_values(age)
    # If age is "25", returns 25 (numeric)
    # If age is "hello", returns "hello" (character, not convertible)

    # Force numeric conversion (may produce NA):
    val <- sd_values(some_field, as_numeric = TRUE)
    # "123" becomes 123, "hello" becomes NA

    # Never convert to numeric (e.g., ZIP codes with leading zeros):
    zip <- sd_values(zip_code, as_numeric = FALSE)
    # "01234" stays as "01234", not converted to 1234

    # Default behavior (NULL) auto-detects pipe and splits:
    fruits <- sd_values(fav_fruits)
    # If value is "apple|banana|orange", returns c("apple", "banana", "orange")
    # If value is "apple", returns "apple" (no pipe, no split)

    # Force split (even if no pipe present):
    vals <- sd_values(some_field, as_vector = TRUE)

    # Never split (keep as single string):
    raw <- sd_values(fav_fruits, as_vector = FALSE)
    # "apple|banana|orange" stays as "apple|banana|orange"

    # Check number of selections:
    if (length(sd_values(fav_fruits)) > 3) {
      # User selected more than 3 fruits
    }

    # Check if specific option was selected:
    if ("apple" %in% sd_values(fav_fruits)) {
      # User selected apple
    }

    sd_server(db = db)
  }
} # }