vyper.exceptions.VariableDeclarationException: line 79:17 Persistent variable undeclared: highstBid
     78     # If bid is less than highest bid, bid fails
---> 79     if (value <= self.highstBid):
-------------------------^
     80         return False

Raises when calling a function with invalid arguments, for example an incorrect number of positional arguments or an invalid keyword argument.

Raises on an illegal function call, such as attempting to call between two external functions.

Raises when an array index is out of bounds.

Raises when an event declaration is invalid.

Raises when a contract contains an action that cannot be performed with the active EVM ruleset.

Raises when a function declaration is invalid, for example because of incorrect or mismatched return values.

Raises when attempting to perform a change a variable, constant or definition that cannot be changed. For example, trying to update a constant, or trying to assign to a function definition.

Raises when an interface is not fully implemented.

Raises on a reference to an attribute that does not exist.

Raises when no valid type can be found for a literal value.

.. code-block:: vyper

    #pragma enable-decimals

    @external
    def foo():
        bar: decimal = 3.123456789123456789

This example raises ``InvalidLiteral`` because the given literal value has too many decimal places and so cannot be assigned any valid Vyper type.

Raises when using an invalid operator for a given type.

.. code-block:: vyper

    @external
    def foo():
        a: String[10] = "hello" * 2

This example raises ``InvalidOperation`` because multiplication is not possible on string types.

Raises on an invalid reference to an existing definition.

.. code-block:: vyper

    baz: int128

    @external
    def foo():
        bar: int128 = baz

This example raises ``InvalidReference`` because ``baz`` is a storage variable. The reference to it should be written as ``self.baz``.

Raises when using an invalid literal value for the given type.

.. code-block:: vyper

    @external
    def foo():
        bar: int128 = 3.5

This example raises ``InvalidType`` because ``3.5`` is a valid literal value, but cannot be cast as ``int128``.

Raises when the compiler JSON input is malformed.

Raises when attempting to assign a variable to a name that is already in use.

Raises when a contract contains an invalid :ref:`NatSpec<natspec>` docstring.

.. code-block:: python

    vyper.exceptions.SyntaxException: line 14:5 No description given for tag '@param'
         13     @dev the feet are sticky like rice
    ---> 14     @param
    -------------^
         15     @return always True

Raises when attempting to access ``msg.value`` from within a function that has not been marked as ``@payable``.

.. code-block:: vyper

    @external
    def _foo():
        bar: uint256 = msg.value

Raises when a numeric value is out of bounds for the given type.

Raises when attempting to perform a modifying action within view-only or stateless context. For example, writing to storage in a ``@view`` function, reading from storage in a ``@pure`` function.

Raises on syntax that is parsable, but invalid in some way.

.. code-block:: python

    vyper.exceptions.StructureException: line 181:0 Invalid top-level statement
         180
    ---> 181 '''
    ---------^
         182

Raises on invalid syntax that cannot be parsed.

.. code-block:: python

    vyper.exceptions.SyntaxException: line 4:20 invalid syntax
            3 struct Bid:
    ---> 4   blindedBid bytes32
    ---------------------------^
            5   deposit: uint256

Raises when attempting to perform an action between two or more objects with incompatible types.

.. code-block:: vyper

    #pragma enable-decimals

    @external
    def foo():
        bar: int128 = 3
        baz: decimal = 4.2

        if baz + bar > 4:
            pass

``bar`` has a type of ``int128`` and ``baz`` has a type of ``decimal``, so attempting to add them together raises a ``TypeMismatch``.

Raises when attempting to access an object that has not been declared.

Raises on an invalid variable declaration.

.. code-block:: bash

    vyper.exceptions.VariableDeclarationException: line 79:17 Persistent variable undeclared: highstBid
         78     # If bid is less than highest bid, bid fails
    ---> 79     if (value <= self.highstBid):
    -------------------------^
         80         return False

Raises when a contract version string is malformed or incompatible with the current compiler version.

Raises when a divide by zero or modulo zero situation arises.

.. code:: shell

    $ vyper v.vy
    Error compiling: v.vy
    vyper.exceptions.CompilerPanic: Number of times repeated
    must be a constant nonzero positive integer: 0 Please create an issue.

A compiler panic error indicates that there is a problem internally to the compiler and an issue should be reported right
away on the Vyper Github page.  Open an issue if you are experiencing this error. Please `Open an Issue <https://github.com/vyperlang/vyper/issues>`_