as: Flonums
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1 3.6.2.3 Flonums
1 ...............
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1 A "flonum" represents a floating point number. The translation is
1 indirect: a decimal floating point number from the text is converted by
1 'as' to a generic binary floating point number of more than sufficient
1 precision. This generic floating point number is converted to a
1 particular computer's floating point format (or formats) by a portion of
1 'as' specialized to that computer.
1
1 A flonum is written by writing (in order)
1 * The digit '0'. ('0' is optional on the HPPA.)
1
1 * A letter, to tell 'as' the rest of the number is a flonum. 'e' is
1 recommended. Case is not important.
1
1 On the H8/300, Renesas / SuperH SH, and AMD 29K architectures, the
1 letter must be one of the letters 'DFPRSX' (in upper or lower
1 case).
1
1 On the ARC, the letter must be one of the letters 'DFRS' (in upper
1 or lower case).
1
1 On the Intel 960 architecture, the letter must be one of the
1 letters 'DFT' (in upper or lower case).
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1 On the HPPA architecture, the letter must be 'E' (upper case only).
1
1 * An optional sign: either '+' or '-'.
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1 * An optional "integer part": zero or more decimal digits.
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1 * An optional "fractional part": '.' followed by zero or more decimal
1 digits.
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1 * An optional exponent, consisting of:
1
1 * An 'E' or 'e'.
1 * Optional sign: either '+' or '-'.
1 * One or more decimal digits.
1
1 At least one of the integer part or the fractional part must be
1 present. The floating point number has the usual base-10 value.
1
1 'as' does all processing using integers. Flonums are computed
1 independently of any floating point hardware in the computer running
1 'as'.
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