tapscript: fix minor typo

1 files changed, 1 insertions, 1 deletions

diff --git a/bip-tapscript.mediawiki b/bip-tapscript.mediawiki
index 37e217b..d4cd5da 100644
--- a/bip-tapscript.mediawiki
+++ b/bip-tapscript.mediawiki
@@ -53,7 +53,7 @@ The rules below only apply when validating a transaction input for which all of
 Validation of such inputs must be equivalent to performing the following steps in the specified order.
 # If the input is invalid due to BIP141 or bip-taproot, fail.
 # The script as defined in bip-taproot (i.e., the penultimate witness stack element after removing the optional annex) is called the '''tapscript''' and is decoded into opcodes, one by one:
-## If any opcode numbered ''80, 98, 126-129, 131-134, 137-138, 141-142, 149-153, 187-254'' is encountered, validation succeeds (none of the rules below apply). This is true even if later bytes in the tapscript would fail to decode otherwise. These opcodes are renamed to <code>OP_SUCCESS80</code>, ..., <code>OP_SUCCESS254</code>, and collectively known as <code>OP_SUCCESSx</code><ref>'''<code>OP_SUCCESSx</code>''' <code>OP_SUCCESSx</code> is a mechanism to upgrade the Script system. Using an <code>OP_SUCCESSx</code> before its meaning is defined by a softfork is insecure and leads to fund loss. The inclusion of <code>OP_SUCCESSx</code> in a script will pass it unconditionally. It precedes any script execution rules to avoid the difficulties in specifying various edge cases, for example: <code>OP_SUCCESSx</code> in a script with an input stack larger than 1000 elements, <code>OP_SUCCESSx</code> after too many signature opcodes, or even scripts with conditionals lacking <code>OP_ENDIF</code>. The mere existence of an <code>OP_SUCCESSx</code> anywhere in the script will guarantee a pass for all such cases. <code>OP_SUCCESSx</code> are similar to the <code>OP_RETURN</code> in very early bitcoin versions (v0.1 up to and including v0.3.5). The original <code>OP_RETURN</code> terminates script execution immediately, and return pass or fail based on the top stack element at the moment of termination. This was one of a major design flaws in the original bitcoin protocol as it permitted unconditional third party theft by placing an <code>OP_RETURN</code> in <code>scriptSig</code>. This is not a concern in the present proposal since it is not possible for a third party to inject an <code>OP_SUCCESSx</code> to the validation process, as the <code>OP_SUCCESSx</code> is part of the script (and thus committed to be the taproot output), implying the consent of the coin owner. <code>OP_SUCCESSx</code> can be used for a variety of upgrade possibilities:
+## If any opcode numbered ''80, 98, 126-129, 131-134, 137-138, 141-142, 149-153, 187-254'' is encountered, validation succeeds (none of the rules below apply). This is true even if later bytes in the tapscript would fail to decode otherwise. These opcodes are renamed to <code>OP_SUCCESS80</code>, ..., <code>OP_SUCCESS254</code>, and collectively known as <code>OP_SUCCESSx</code><ref>'''<code>OP_SUCCESSx</code>''' <code>OP_SUCCESSx</code> is a mechanism to upgrade the Script system. Using an <code>OP_SUCCESSx</code> before its meaning is defined by a softfork is insecure and leads to fund loss. The inclusion of <code>OP_SUCCESSx</code> in a script will pass it unconditionally. It precedes any script execution rules to avoid the difficulties in specifying various edge cases, for example: <code>OP_SUCCESSx</code> in a script with an input stack larger than 1000 elements, <code>OP_SUCCESSx</code> after too many signature opcodes, or even scripts with conditionals lacking <code>OP_ENDIF</code>. The mere existence of an <code>OP_SUCCESSx</code> anywhere in the script will guarantee a pass for all such cases. <code>OP_SUCCESSx</code> are similar to the <code>OP_RETURN</code> in very early bitcoin versions (v0.1 up to and including v0.3.5). The original <code>OP_RETURN</code> terminates script execution immediately, and return pass or fail based on the top stack element at the moment of termination. This was one of a major design flaws in the original bitcoin protocol as it permitted unconditional third party theft by placing an <code>OP_RETURN</code> in <code>scriptSig</code>. This is not a concern in the present proposal since it is not possible for a third party to inject an <code>OP_SUCCESSx</code> to the validation process, as the <code>OP_SUCCESSx</code> is part of the script (and thus committed to by the taproot output), implying the consent of the coin owner. <code>OP_SUCCESSx</code> can be used for a variety of upgrade possibilities:
 * An <code>OP_SUCCESSx</code> could be turned into a functional opcode through a softfork. Unlike <code>OP_NOPx</code>-derived opcodes which only have read-only access to the stack, <code>OP_SUCCESSx</code> may also write to the stack. Any rule changes to an <code>OP_SUCCESSx</code>-containing script may only turn a valid script into an invalid one, and this is always achievable with softforks.
 * Since <code>OP_SUCCESSx</code> precedes size check of initial stack and push opcodes, an <code>OP_SUCCESSx</code>-derived opcode requiring stack elements bigger than 520 bytes may uplift the limit in a softfork.
 * <code>OP_SUCCESSx</code> may also redefine the behavior of existing opcodes so they could work together with the new opcode. For example, if an <code>OP_SUCCESSx</code>-derived opcode works with 64-bit integers, it may also allow the existing arithmetic opcodes in the ''same script'' to do the same.