Difference between revisions of "period"

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Numbers noted in a non-decimal base can not be noted in that way.
 
Numbers noted in a non-decimal base can not be noted in that way.
E.g. a half can not be written as <syntaxhighlight lang="pascal" enclose="none">%0.1</syntaxhighlight> ([[Percent_sign|<syntaxhighlight lang="pascal" enclose="none">%</syntaxhighlight>]] being the prefix marking [[ Binary numeral system|binary numbers]]).
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E.g. a half can not be written as <syntaxhighlight lang="pascal" enclose="none">%0.1</syntaxhighlight> ([[Percent sign|<syntaxhighlight lang="pascal" enclose="none">%</syntaxhighlight>]] being the prefix marking [[Binary numeral system|binary numbers]]).
  
 
== identifier scope selector ==
 
== identifier scope selector ==
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== namespaces ==
 
== namespaces ==
  
Unit names with dots create namespace symbol.
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Unit names containing dots create namespaces.
  
 
== ASCII value ==
 
== ASCII value ==
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{{Symbols}}
 
{{Symbols}}
 +
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[[Category:Code]]

Revision as of 13:54, 23 April 2018

English (en) suomi (fi) français (fr)

radix mark

Pascal uses the . (dot) to separate the integer and fractional part in literal decimal integers.

myReal := 6.28318

At least one digit in front of the period is mandatory. A 0 integer part must not be omitted.

Numbers noted in a non-decimal base can not be noted in that way. E.g. a half can not be written as %0.1 (% being the prefix marking binary numbers).

identifier scope selector

For structured data types the dot separates the data structure identifier from its individual components, i.e. methods or data fields.

 1program recordDemo(input, output, stderr);
 2
 3uses
 4	Linux;
 5
 6var
 7	info: TSysInfo;
 8begin
 9	if sysInfo(@info) <> 0 then
10	begin
11		halt(1);
12	end;
13	
14	writeLn('uptime: ', info.uptime, ' seconds');
15	
16	with info do
17	begin
18		writeLn('total free: ', freeram, ' bytes');
19	end;
20end.

range

Two consecutive dots .. let you specify an integer sub-range.

type
	signumCodomain = -1..1;


module end

The main block of any module, i.e. program, unit or library, has to be closed with an end “dot”:

program hiWorld(input, output, stderr);

begin
	writeLn('Hi world!');
end.

It can be seen as an adoption of natural (written) languages, where a full stop marks an end of a sentence.

Anything else after the final end., assuming syntactical correctness, will be ignored by the compiler.


namespaces

Unit names containing dots create namespaces.

ASCII value

In ASCII, the character code decimal 46 (or hexadecimal 2E) is defined to be . (full stop).


navigation bar: topic: Pascal symbols
single characters

+ (plus)  •  - (minus)  •  * (asterisk)  •  / (slash)
= (equal)  •  > (greater than)  •  < (less than)
. (period)  •  : (colon)  •  ; (semi colon)
^ (hat)  •  @ (at)
$ (dollar sign)  •  & (ampersand)  •  # (hash)
' (single quote)

character pairs

<> (not equal)  •  <= (less than or equal)  •  := (becomes)  •  >= (greater than or equal)

 •  >< (symmetric difference)  •  // (double slash)