diff options
Diffstat (limited to 'txr.1')
| -rw-r--r-- | txr.1 | 47 |
1 files changed, 43 insertions, 4 deletions
@@ -3503,7 +3503,7 @@ merged into the surrounding syntax. \*(TX supports integers and floating-point numbers. -An integer constant is made up of digits +An integer literal is made up of digits .code 0 through .codn 9 , @@ -3512,6 +3512,12 @@ optionally preceded by a or .code - sign. +The character +.code , +(comma) may appear between digits, as a visual separator of no semantic significance. +The digit sequence must start and end with a digit. +Runs of consecutive commas are permitted. Commas outside of the digit sequence +are interpreted as the Lisp unquote syntax. Examples: @@ -3521,6 +3527,16 @@ Examples: +0 -0 +234483527304983792384729384723234 + -1,000,000,001 + 1,2,3,,4 ;; equivalent to 1234 +.brev + +Examples that are not integer tokens: + +.verb + ,123 ;; equivalent to (sys:unquote 123) + 123,a ;; equivalent to 123, followed by (sys:unquote a) + -,1 ;; symbol - followed by (sys:unquote 1) .brev An integer constant can also be specified in hexadecimal using the prefix @@ -3539,12 +3555,20 @@ through #x-ABC ;; -2748 .brev +These digits may contain separator commas, just as in the case +of the decimal integer: + +.verb + #xFFFF,FFFF,FFFF +.brev + Similarly, octal numbers are supported with the prefix .code #o followed by octal digits: .verb - #o777 ;; 511 + #o777 ;; 511 + #o123,456 ;; 42797 .brev and binary numbers can be written with a @@ -3552,14 +3576,23 @@ and binary numbers can be written with a prefix: .verb - #b1110 ;; 14 + #b1110 ;; 14 + #b1111,1111 ;; 255 +.brev + +A comma between the radix prefix and digits is +a syntax error: + +.verb + #x,DEF5,549C ;; Syntax error + #b,1001,1101 ;; Likewise .brev Note that the .code #b prefix is also used for buffer literals. -A floating-point constant is marked by the inclusion of a decimal point, the +A floating-point literal is marked by the inclusion of a decimal point, the scientific E notation, or both. It is an optional sign, followed by a mantissa consisting of digits, a decimal point, more digits, and then an optional E notation consisting of the letter @@ -3575,6 +3608,10 @@ In the mantissa, the digits are not optional. At least one digit must either precede the decimal point or follow it. That is to say, a decimal point by itself is not a floating-point constant. +The digits of the mantissa may include separator commas, in the same manner as decimal +integer literals, in both the integer and fractional part. The digits of the +exponent may not include separator commas. + Examples: .verb @@ -3587,6 +3624,7 @@ Examples: -.5 +3E+3 1.E5 + 1,123,456.935,342E+013 .brev Examples which are not floating-point constant tokens: @@ -3598,6 +3636,7 @@ Examples which are not floating-point constant tokens: 1.0E ;; syntax error: invalid floating point constant 1.E ;; syntax error: invalid floating point literal .e ;; syntax error: dot token followed by symbol + ,1.0 ;; equivalent to (sys:unquote 1.0) .brev In \*(TX there is a special "dotdot" token consisting of two consecutive periods. |