StringEquals
[b, a] → [String(b) === String(a)]

Adobe documentation

ActionStringEquals

ActionStringEquals tests two strings for equality.

FieldTypeComment
ActionStringEqualsACTIONRECORDHEADERActionCode = 0x13

ActionStringEquals does the following:

  1. Pops value A off the stack.
  2. Pops value B off the stack.
  3. Compares A and B as strings.( The comparison is case-sensitive)
  4. If the strings are equal, true is pushed to the stack for SWF 5 and later (SWF 4 pushes 1).
  5. Otherwise, false is pushed to the stack for SWF 5 and later (SWF 4 pushes 0).