Annotated Ada Reference ManualLegal Information
Contents   Index   References   Search   Previous   Next 

F.3.2 Edited Output Generation

Dynamic Semantics

1
The contents of an edited output string are based on: 
2
3
4
5
6
7
8
9
The combination of a True value for Blank_When_Zero and a '*' character in Pic_String is inconsistent; no edited output string is defined. 
9.a/2
Reason: {AI95-00114-01} Such a Pic_String is invalid, and any attempt to use such a string will raise Picture_Error. 
10
A layout error is identified in the rules below if leading non-zero digits of Item, character values of the Currency string, or a negative sign would be truncated; in such cases no edited output string is defined.
11
The edited output string has lower bound 1 and upper bound N where N = Pic_String'Length + Currency_Length_Adjustment – Radix_Adjustment, and 
12
13
14
{displayed magnitude (of a decimal value)} Let the magnitude of Item be expressed as a base-10 number Ip···I1.F1···Fq, called the displayed magnitude of Item, where: 
15
16
17
If n < Num'Scale, then the above number is the result of rounding (away from 0 if exactly midway between values).
18
If Blank_When_Zero = True and the displayed magnitude of Item is zero, then the edited output string comprises all space character values. Otherwise, the picture String is treated as a sequence of instances of syntactic categories based on the rules in F.3.1, and the edited output string is the concatenation of string values derived from these categories according to the following mapping rules.
19
Table F-1 shows the mapping from a sign control symbol to a corresponding character or string in the edited output. In the columns showing the edited output, a lower-case 'b' represents the space character. If there is no sign control symbol but the value of Item is negative, a layout error occurs and no edited output string is produced.
Table F-1: Edited Output for Sign Control Symbols
Sign Control SymbolEdited Output for
Non-Negative Number
Edited Output for
Negative Number
'+''+''–'
'–''b''–'
'<''b''('
'>''b'')'
"CR""bb""CR"
"DB""bb""DB"
20
An instance of fixed_LHS_sign maps to a character as shown in Table F-1.
21
An instance of fixed_$_char maps to Currency.
22
An instance of direct_insertion maps to Separator if direct_insertion = '_', and to the direct_insertion Character otherwise.
23
An instance of number maps to a string integer_part & radix_part & fraction_part where: 
24
25
1.
Occurrences of '9' in fore_digits of number are replaced from right to left with the decimal digit character values for I1, ..., Ip, respectively.
26
2.
Each occurrence of '9' in fore_digits to the left of the leftmost '9' replaced according to rule 1 is replaced with '0'.
27
3.
If p exceeds the number of occurrences of '9' in fore_digits of number, then the excess leftmost digits are eligible for use in the mapping of an instance of zero_suppression, floating_LHS_sign, floating_$_currency, or floating_#_currency to the left of number; if there is no such instance, then a layout error occurs and no edited output string is produced. 
28
29
30
31
32
1.
Occurrences of '9' in aft_digits of number are replaced from left to right with the decimal digit character values for F1, ... Fq.
33
2.
Each occurrence of '9' in aft_digits to the right of the rightmost '9' replaced according to rule 1 is replaced by '0'. 
34
An instance of zero_suppression maps to the string obtained as follows: 
35
1.
The rightmost 'Z', 'z', or '*' Character values are replaced with the excess digits (if any) from the integer_part of the mapping of the number to the right of the zero_suppression instance,
36
2.
A context_sensitive_insertion Character is replaced as though it were a direct_insertion Character, if it occurs to the right of some 'Z', 'z', or '*' in zero_suppression that has been mapped to an excess digit,
37
3.
Each Character to the left of the leftmost Character replaced according to rule 1 above is replaced by: 
38
39
40
4.
A layout error occurs if some excess digits remain after all 'Z', 'z', and '*' Character values in zero_suppression have been replaced via rule 1; no edited output string is produced. 
41
An instance of RHS_sign maps to a character or string as shown in Table F-1.
42
An instance of floating_LHS_sign maps to the string obtained as follows. 
43
1.
Up to all but one of the rightmost LHS_Sign Character values are replaced by the excess digits (if any) from the integer_part of the mapping of the number to the right of the floating_LHS_sign instance.
44
2.
The next Character to the left is replaced with the character given by the entry in Table F-1 corresponding to the LHS_Sign Character.
45
3.
A context_sensitive_insertion Character is replaced as though it were a direct_insertion Character, if it occurs to the right of the leftmost LHS_Sign character replaced according to rule 1.
46
4.
Any other Character is replaced by the space character..
47
5.
A layout error occurs if some excess digits remain after replacement via rule 1; no edited output string is produced. 
48
An instance of fixed_#_currency maps to the Currency string with n space character values concatenated on the left (if the instance does not follow a radix) or on the right (if the instance does follow a radix), where n is the difference between the length of the fixed_#_currency instance and Currency'Length. A layout error occurs if Currency'Length exceeds the length of the fixed_#_currency instance; no edited output string is produced.
49
An instance of floating_$_currency maps to the string obtained as follows: 
50
1.
Up to all but one of the rightmost '$' Character values are replaced with the excess digits (if any) from the integer_part of the mapping of the number to the right of the floating_$_currency instance.
51
2.
The next Character to the left is replaced by the Currency string.
52
3.
A context_sensitive_insertion Character is replaced as though it were a direct_insertion Character, if it occurs to the right of the leftmost '$' Character replaced via rule 1.
53
4.
Each other Character is replaced by the space character.
54
5.
A layout error occurs if some excess digits remain after replacement by rule 1; no edited output string is produced. 
55
An instance of floating_#_currency maps to the string obtained as follows: 
56
1.
Up to all but one of the rightmost '#' Character values are replaced with the excess digits (if any) from the integer_part of the mapping of the number to the right of the floating_#_currency instance.
57
2.
The substring whose last Character occurs at the position immediately preceding the leftmost Character replaced via rule 1, and whose length is Currency'Length, is replaced by the Currency string.
58
3.
A context_sensitive_insertion Character is replaced as though it were a direct_insertion Character, if it occurs to the right of the leftmost '#' replaced via rule 1.
59
4.
Any other Character is replaced by the space character.
60
5.
A layout error occurs if some excess digits remain after replacement rule 1, or if there is no substring with the required length for replacement rule 2; no edited output string is produced. 
61
An instance of all_zero_suppression_number maps to: 
62
63
64
65
An instance of all_sign_number maps to: 
66
67
68
An instance of all_currency_number maps to: 
69
70

Examples

71
In the result string values shown below, 'b' represents the space character. 
72
Item:         Picture and Result Strings:
73
123456.78     Picture:  "-###**_***_**9.99"
                        "bbb$***123,456.78"
                        "bbFF***123.456,78" (currency = "FF",
                                             separator = '.',
                                             radix mark = ',')
74/1
{8652/0089} {AI95-00070} 123456.78     Picture:  "-$$$**_***_**9.99"
              Result:   "bbb$***123,456.78"
                       "bbbFF***123.456,78" (currency = "FF",
                                             separator = '.',
                                             radix mark = ',')
75
0.0          Picture: "-$$$$$$.$$"
             Result:  "bbbbbbbbbb"
76
0.20         Picture: "-$$$$$$.$$"
             Result:  "bbbbbb$.20"
77
-1234.565    Picture: "<<<<_<<<.<<###>"
             Result:  "bb(1,234.57DMb)"  (currency = "DM")
78
12345.67     Picture: "###_###_##9.99"
             Result:  "bbCHF12,345.67"   (currency = "CHF")

Wording Changes from Ada 95

78.a/2
{8652/0089} {AI95-00070-01} Corrigendum: Corrected the picture string example. 

Contents   Index   References   Search   Previous   Next 
Ada-Europe Sponsored by Ada-Europe