The Fortress Language Specification - CiteSeerX

40.5.1 coercion int r(x:IntegerStaticr) where { −2 b−1 ≤ r < 2 b }
An static integer may be coerced to a binary word that corresponds to that integer value when interpreted as either a
signed integer or an unsigned integer. For example, the type BinaryWord3 has 2 (23) = 256 distinct binary word
values; when they are interpreted as signed integers, the integer values range from −128 to 127, and when they are
interpreted as unsigned integers, the integer values range from 0 to 255. Therefore any static integer from −128 to
255 may be coerced to type BinaryWord3 .
40.5.2 coercion bool bigEndianBytes,bool bigEndianBits
(x:BinaryEndianWordb,bigEndianBytes,bigEndianBits)
Any binary endian word may be coerced to a plain binary word of the same size and value. In effect, this coercion
merely discards the endianness information.
40.5.3 coercion nat b ′ ,nat n,bool bigEndianSequence
(x:BinaryLinearEndianSequenceb ′ , n,bigEndianSequence)
where { 2 b = n · 2 b′ }
A binary linear endian sequence of smaller binary words may be coerced to a single binary word, provided that the
length of the linear sequence is an appropriate power of two, so that the total number of bits in the sequence is the
same as the total number of bits in the resulting binary word. The manner in which the elements of the sequence are
used to form the new binary word value respects the endianness of the sequence, so that element 0 of the sequence
supplies the most significant bits of the result if bigEndianSequence is true, but supplies the least significant bits of
the result if bigEndianSequence is false.
40.5.4 coercion nat b ′ ,bool bigEndianBytes,bool bigEndianBits,nat n,bool bigEndianSequence
(x:BinaryEndianLinearEndianSequenceb ′ ,bigEndianBytes,bigEndianBits,
n,bigEndianSequence)
where { 2 b = n · 2 b′ }
A binary endian linear endian sequence of smaller binary endian words may be coerced to a single binary word,
provided that the length of the linear sequence is an appropriate power of two, so that the total number of bits in the
sequence is the same as the total number of bits in the resulting binary word. The manner in which the elements of
the sequence are used to form the new binary word value respects the endianness of the sequence, so that element 0
of the sequence supplies the most significant bits of the result if bigEndianSequence is true, but supplies the least
significant bits of the result if bigEndianSequence is false. In effect, the “bytes and bits” endianness information is
simply ignored and discarded.
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