Display

The <#4292#>display<#4292#> is a construct serving to denote values for composed types (structures and rows) and, in conjunction with the <#4293#>abstractor<#4293#>, for abstract types.

(315,060)<#4651#> (000,050)<#4601#>display<#4601#> 258 (000,030)<#4602#>(1,0)<#4295#>030<#4295#> <#5820#>(010,010)<#5823#>[<#5823#><#5820#> (010,010) (1,0)<#4298#>030<#4298#><#5825#>#tex2html_wrap7829#(080,010)<#5826#>expression<#5826#><#5825#> (1,0)<#4301#>030<#4301#> <#5832#>(010,010)<#5835#>]<#5835#><#5832#> (010,010) (1,0)<#4304#>030<#4304#><#4602#> 259 (155,020)<#4305#>(20,20)[r]<#4305#> (155,010)<#4603#>(-1,0)<#4306#>040<#4306#><#4603#> (065,010)<#4604#>(1,0)<#4307#>040<#4307#> <#5841#>(010,010)<#5844#>,<#5844#><#5841#> (010,010) <#4604#> (065,020)<#4310#>(20,20)[l]<#4310#> 260 <#4651#>

If the <#4311#>display<#4311#> is used to denote a row, the number of its constituent <#4312#>expressions<#4312#> has to be equal to the <#4313#>cardinality<#4313#> of the row, whereas each <#4314#>expression<#4314#> has to be of the type of the elements of the row.

If the <#4315#>display<#4315#> is used to denote a structure, the number of its constituent <#4316#>expressions<#4316#> has to be the same as the number of <#4317#>fields<#4317#> of the structure, whereas each <#4318#>expression<#4318#> has to be of the type of the corresponding field of the structure.

The <#4319#>display<#4319#> is executed by executing its constituent <#4320#>expressions<#4320#> collaterally, and composing a composed object from the values in their textual order.

#./h04.tex# #./h05.tex#