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Reviewer: Arvid G. Larson

The Process and Experimental Automation Realtime Language (PEARL) is one of a number of general-purpose high-order programming languages that has been developed for use in real time process control applications. Initiated in 1969 with the support of the Ministry of Research and Technology of the Federal Republic of Germany, a Basic PEARL standard was first published in 1981 [1]. It has since been implemented on a handful of generally smaller process-control-oriented computer systems, mostly within the European scientific and industrial community. A Full PEARL language standard has been developed. This text is the English translation of a reference manual describing a subset of Full PEARL as developed by the authors. This manual follows normal form for such reference documents, consisting of three basic parts: an overview of unique PEARL features compared to “older” high-order process-control languages (e.g., versions of PL/I); the language syntax and semantic rules and constructions; and a discussion of language features necessary to achieve various application operations. Examples of language use, which are spread throughout the text, tend to be terse but adequate. Little if any discussion is provided concerning provisions for machine dependence or implementation-specific constructions and constraints which so often impede high-order language use in real time application. The reader would thus require a second runtime operations manual to actually exercise PEARL or to assess its process-control operations limitations in any given implementation environment. Two of several Appendices describe this PEARL version's extensions over the Basic PEARL standard, as well as its limitations with respect to the Full PEARL standard. In all, this text is found to be a brief but sufficient language reference manual. One drawback is that it has apparently been translated from the German text without the benefit of an English editor. It is at times awkward to read, but the authors' points, as well as language fundamentals necessary for a comparative understanding of PEARL, tend to come through in spite of this obstacle.