diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/ChangeLog | 5 | ||||
| -rw-r--r-- | src/algebra/data.spad.pamphlet | 32 |
2 files changed, 20 insertions, 17 deletions
diff --git a/src/ChangeLog b/src/ChangeLog index 70fc6021..3fd40052 100644 --- a/src/ChangeLog +++ b/src/ChangeLog @@ -1,3 +1,8 @@ +2008-10-02 Gabriel Dos Reis <gdr@cs.tamu.edu> + + * algebra/data.spad.pamphlet (Byte): Add coercion to and from + Character. + 2008-10-01 Gabriel Dos Reis <gdr@cs.tamu.edu> * interp/i-spec1.boot (upcase): Tidy. diff --git a/src/algebra/data.spad.pamphlet b/src/algebra/data.spad.pamphlet index fff04339..b491d001 100644 --- a/src/algebra/data.spad.pamphlet +++ b/src/algebra/data.spad.pamphlet @@ -23,46 +23,44 @@ import OutputForm ++ Description: ++ Byte is the datatype of 8-bit sized unsigned integer values. Byte(): Public == Private where - Public == Join(OrderedSet, CoercibleTo NonNegativeInteger) with + Public == Join(OrderedSet, CoercibleTo NonNegativeInteger, + CoercibleTo Character) with byte: NonNegativeInteger -> % ++ byte(x) injects the unsigned integer value `v' into ++ the Byte algebra. `v' must be non-negative and less than 256. coerce: NonNegativeInteger -> % ++ coerce(x) has the same effect as byte(x). + coerce: Character -> % + ++ coerce(c) views `c' a a byte. In particular `c' is supposed + ++ to have a numerical value less than 256. bitand: (%,%) -> % ++ bitand(x,y) returns the bitwise `and' of `x' and `y'. bitior: (%,%) -> % ++ bitor(x,y) returns the bitwise `inclusive or' of `x' and `y'. Private == add + import Character byte(x: NonNegativeInteger): % == not (x < 256$Lisp) => userError "integer value cannot be represented by a byte" x : % - hash x == - SXHASH(x)$Lisp + hash x == SXHASH(x)$Lisp - coerce(x: NonNegativeInteger): % == - byte x + coerce(x: NonNegativeInteger): % == byte x + coerce(x: %): NonNegativeInteger == x : NonNegativeInteger - coerce(x: %): NonNegativeInteger == - x : NonNegativeInteger + coerce(c: Character) == ord(c)::% + coerce(x: %): Character == char(x::NonNegativeInteger) coerce(x: %): OutputForm == x::NonNegativeInteger::OutputForm - x = y == - byteEqual(x,y)$Lisp - - x < y == - byteLessThan(x,y)$Lisp - - bitand(x,y) == - bitand(x,y)$Lisp + x = y == byteEqual(x,y)$Lisp + x < y == byteLessThan(x,y)$Lisp - bitior(x,y) == - bitior(x,y)$Lisp + bitand(x,y) == bitand(x,y)$Lisp + bitior(x,y) == bitior(x,y)$Lisp @ |