Hi Rony,
Missatge de Rony G. Flatscher <rony.flatsc...@wu.ac.at> del dia dg., 9 de març 2025 a les 11:40: > 1) ad stem arrays > ============== > > Stem arrays have been conceived and used since the inception of Rexx. > > The pattern is simple: the tail is an integer number from 1 on, the tail > with the value 0 keeps the current number of total stem array elements. > E.g.: > > a.1="one" > a.2="two" > a.0=2 > say "there are" a.0 "items" > > Turning such a stem array into an ooRexx array should yield an array that > omits the element with the tail 0 and uses the tail's number as index in > the ooRexx array. E.g. turning the above stem array into an ooRexx array: > > a[1]="one" > a[2]="two" > say "there are" a~itmes "items" > > 1a) In order to create an ooRexx array from a stem array the following > method should be added to the stem class: > > makeArrayFromStemArray > > This name makes it clear that a stem array is to be processed and that the > resulting array should not have the stem value with the tail 0. > (The existting stem method makeArray continues to create an array that > represents all tails of a stem, including a tail with the value 0.) > I'm not sure that using "makeXXX" for the message names is a good idea, because the request method of the Object class uses the "make" pattern for class conversions. I'd also try to choose a shorter name (long names are difficult to remember). Some things that should be defined: - What happens when not all tails have a value? For example, if s.= 'Default", s.0 = 3, s.1 = 'X", s.2 does not have a value, s.3 = "Z", and a is the converted array, what should be the value of a[2]? Both "Default" and .Nil are reasonable answers to this question. - What happens when the stem has values that are not part of the array, like s.this = "that"? - When s.0 is not a positive integer, a syntax error should be raised. 1b) In order to create a stem from an ooRexx array the following method > should be added to the array class: > > makeStemArray > > This name makes it clear that a stem array is to be created from the array > items (using the array index values as tails) and adding the 0 tail to > indicate the number of stem elements. > Maybe in this case we could use makeStem directly, as there is no prior method with that name? Also: what happens when the array is multi-dimensional? One would think of using several stem indexes, as in s.1.4.2 = "value", but then it becomes unclear where to store the dimensions. > --- > > 2) ad using the array class for reading and writing files/streams directly > ========================================================== > > The ooRexx stream class has a method arrayin to allow reading the content > of a stream into an ooRexx array, and arrayout to write the content of an > array to a stream. In order to use these methods a stream instance must be > created first before being able to use the arrayin and arrayout methods and > closing the stream thereafter. As the purpose of these two methods is to > simply get the content into and from an array, it may be cumbersome to > explicitly have to open and close streams in order to just read into or > write the content of an array. > > In order to forego the need to create stream instances in order to read > the content into an array or an array into a stream or file two class > methods for the ooRexx array class are proposed: > > 2a) In order to read the content of a stream or a file with a single > message into an array the following method should be added to the array > class: > > arrayin(filename|stream|file[, Lines|chars) > > This allows for supplying either a filename (string), an instance of .File > or .Stream and optionally "Lines" (default, one array element per text > line) or "chars" (one array element per character). > > 2b) In order to write the content of an array to a file or a stream the > following method should be added to the array class: > > arrayOut(filename|stream|file[, Lines|chars) > > This allows for supplying either a filename (string), an instance of .File > or .Stream and optionally "Lines" (default, a text line per per array > element) or "chars" (the characters of all array elements, without > appending endoflines). > +1 Josep Maria > --- > > Any comments, thoughts? > > ---rony > > _______________________________________________ > Oorexx-devel mailing list > Oorexx-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/oorexx-devel >
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