Validates that images and visualizations have alternative text descriptions.
Required for WCAG 1.1.1 (Non-text Content).
Note: Decorative images should use empty alt text (alt="") to indicate
they should be ignored by assistive technology.
Usage
check_alt_text(alt_text, element_type = "image", decorative = FALSE)
Arguments
- alt_text
Alternative text description
- element_type
Type of element (e.g., "plot", "image", "icon")
- decorative
Logical, TRUE if element is purely decorative
Value
Logical TRUE if valid, FALSE with warning if missing/inadequate
Examples
if (FALSE) { # \dontrun{
check_alt_text("Bar chart showing word frequency", "plot") # TRUE
check_alt_text("", "plot") # FALSE (informative content needs alt text)
check_alt_text("", "icon", decorative = TRUE) # TRUE (decorative is OK)
} # }
