Module failure 

The sentences a program stops with, written once for every tier.

This is the lowest crate every engine and every compiled program links, so a runtime failure’s wording lives here and nowhere else: the interpreter and the VM report these strings, the generated Rust panics with them, and the hosts written in other languages are generated from them (logicaffeine_compile::semantics::failcode).

A broken contract (Require that c, otherwise r.) reports its reason, which must be Text. Every engine refuses a non-Text reason with the same sentence, naming the LOGOS type it got, so the compiled tier routes the reason value through contract_reason. A type with no implementation here does not compile — never a report in the wrong words.

Constants

BITAND_OPERANDS

The reason & stops a program: an operand it has no bits for (a negative big integer, a big integer beside a value that is not a low mask 2^k - 1, or a kind & does not combine).

BITOR_OPERANDS

The reason | stops a program: a big integer, or a kind | does not combine.

BITXOR_OPERANDS

The reason ^ (xor) stops a program: a big integer, or a kind it does not combine.

CALL_DEPTH_EXCEEDED

The reason a program stops when its calls nest deeper than its stack holds: the interpreter and the VM at their call-depth limit, a compiled program at the end of its stack.

DIVIDE_BY_ZERO_QUANTITY

A quantity divided by a quantity whose magnitude is zero.

DIVIDE_MONEY_BY_ZERO

Money divided by the number zero.

DIVIDE_MONEY_BY_ZERO_AMOUNT

Money divided by money whose amount is zero.

DIVIDE_QUANTITY_BY_ZERO

A quantity divided by the number zero.

DIVISION_BY_ZERO

The reason an integer division by zero stops a program.

INT_TOO_WIDE

The reason a compiled program stops when an integer past a machine word reaches a place it holds one.

MODULO_BY_ZERO

The reason an integer remainder by zero stops a program.

MODULUS_NOT_POSITIVE

modular(v, m) with m <= 0.

NO_EXCHANGE_RATES

A conversion with no rates in scope at all.

NO_MODULAR_INVERSE

A modular division whose divisor shares a factor with the modulus.

SET_FIELD_ON_NON_RECORD

The stop for setting a field of a value that is not a record.

SHL_OPERANDS

The reason a left shift stops a program: an operand that is not a machine-word integer.

SHR_OPERANDS

The reason a right shift stops a program: an operand that is not a machine-word integer.

Traits

ContractReason

A value that can stand after otherwise.

FailureText

A value as a failure sentence names it: exactly as Show prints it.

Functions

answered

The value an operation of the exact extension answered, or the stop its refusal names: the sentence the interpreter reports for the same operation on the same values.

cannot_convert

convert(q, unit) to a unit of another dimension: the quantity’s own unit and the one asked for.

cannot_read_bytes

readBytes(path) on a file that cannot be read, with the reason the system gave.

contract_reason

The report a broken contract stops with.

currencies_differ

verb (add, subtract, compare) applied to money in two currencies.

decimal_needs_text_or_int

decimal(…) given a value of another kind than Text, Int or Decimal, named as the engines name it.

field_access_on

The stop for reading a field of a value that is not a record: a value of type_name.

found

The value a map lookup found for key, or the stop key_not_found names.

index_out_of_bounds

The reason an index outside a sequence or a text stops a program: the index as the program wrote it (1-based, or negative from the end).

invalid_utf8

The reason text_from_bytes stops a program whose bytes are not UTF-8: the decoder’s own account of where they stop being it.

invalid_uuid

Text that is not a UUID.

key_not_found

The reason reading a key a map does not hold stops a program: the key as Show prints it.

modular_rings_differ

op (add, subtract, multiply, divide) applied to two residues of different moduli.

no_exchange_rate

A conversion between two currencies with no rate for either in scope.

not_a_decimal

Text decimal(…) cannot read as a base-10 number.

not_a_timestamp

Text that is not an RFC 3339 timestamp.

pop_from_empty

The reason popping a list with no items stops a program: the list as the program writes it (xs, b's items).

quantities_differ

verb (add, subtract) applied to two quantities whose dimensions differ.

quantities_uncomparable

Two quantities compared across dimensions.

unknown_currency

A currency code no currency table holds.

unknown_time_zone

A time zone name no zone table holds.

unknown_unit

A unit name no unit table holds.

uuid_needs_16_bytes

uuid_from_bytes given the wrong number of bytes.