IBM Streams 4.2

Streams Processing Language (SPL) reference

Streams Processing Language (SPL) is a distributed data flow composition language that is used in IBM® Streams. SPL has primitive types, program structures, and definitions that are tailored for streaming data.

Language overview
SPL contains types, expressions, statements, functions, clauses, and other elements of a programming language.
Grammar notation
This language specification adopts a flavor of Backus-Naur Form (BNF) to describe the syntax of language features.
Lexical syntax
SPL defines a set of rules to determine the syntax of a program.
Grammar overview
Here is the SPL grammar syntax, with references to the sections that contain the semantics.
Expression language
Though SPL is a streaming language, there are many places where it uses expressions that are found in traditional imperative or functional languages.
Annotations
Operators can be annotated. Annotations influence the run time behavior of streams processing applications.
Types
SPL has several primitive types that are tailored for streaming, and a few composite types that are inspired by scripting languages but statically checked. The following topics describe the types, how to define them, and how to convert values between different types.
Operators
Operators process tuples in an incoming stream and produce an output stream as a result. SPL supports two kinds of operators: primitive operators and composite operators. A primitive operator is written in C++ or Java™. A composite operator is written in SPL and contains a reusable stream subgraph.
Program structure
Operator config clause
The conﬁg clause specifies hints and directives that influence how the compiler builds an operator invocation, or how the runtime system runs it.

Parent topic: Reference