Syntax Errors

5 Key excerpts on "Syntax Errors"

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  eBook - PDF

  Miscommunications

  Errors, Mistakes, Media

  • Timothy Barker, Maria Korolkova, Timothy Barker, Maria Korolkova(Authors)
  • 2021(Publication Date)
  • Bloomsbury Academic

    (Publisher)

  Programming errors are different from these, because from the computer’s perspective they are not errors at all. The computer executes erroneous code without any problem; it is our interpretation of the output that defines the operation as inaccurate to our expectations. 5 Programming errors have existed since the separation of machines and their program was made. Up to today, programming errors have not become uncommon: “errors belong to the nature of computation” (Trogemann, Viehoff, and Roch 2000: 4). It is assumed that professional programs—programs that have been tested in different stages (with alpha and beta versions) and possibly even been through updates and versioning—only contain two errors in every 1000 lines of code. Normal programs, in contrast, contain twenty-five errors in the same amount of code (cf. Sneed, Baumgartner, and Seidl 2012: 6, 65). The most obvious programming errors are those that discontinue the running program (which appear in the form of a crash and/or the output of an error message): Syntax Errors . They are the result of a wrong use of the orthography or the syntax of a programming language. In the first case, a “word” (command, function, etc.) is mistyped (see Table 16.1, top); the latter is the case if the syntactic construction rules of the specific language are infringed (e.g., not closing loop constructions, wrongly defining jump locations, and not properly terminated command lines). The next level of programming errors are of a semantic nature. They do not cause the program to stop but they lead to an unexpected behavior or output, for example when a wrong function is called correctly. Most programming languages use the “,” to separate different values within a data set and the “.” as the decimal point. A mix‐up of both will lead to semantically unexpected program behavior (see Table 16.1, middle).

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  eBook - ePub

  BCS Glossary of Computing

  • Arnold Burdett, Dan Bowen, Diana Butler, Aline Cumming, Frank Hurvid, Adrian Jackson, John Jaworski, Percy Mett, Thomas Ng, Penny Patterson, Marianne Scheer, Hazel Shaw, Alfred Vella, John Woollard, David Fuller(Authors)
  • 2016(Publication Date)
  • BCS, The Chartered Institute for IT

    (Publisher)

  run-time errors are errors detected during program execution. These errors, such as overflow and division by zero, can occur if a mistake is made in the processing algorithm or as a result of external effects not catered for by the program, such as lack of memory or unusual data.

  Compilation errors are errors detected during compilation and are usually Syntax Errors (see below).

  Linking errors occur when a compiled program is linked to library routines. For example, if a particular subroutine is not present in the library or the number of parameters provided is wrong.

  Syntax Errors occur either when program statements cannot be understood because they do not follow the rules laid down by the programming language, statement Syntax Errors , or when program structures are incorrectly formed, program Syntax Errors or structure errors . Examples of statement Syntax Errors include wrong punctuation and misspelling of reserved words and variables. Examples of program Syntax Errors include control structures incorrectly nested or incorrectly terminated.

  Logical errors are mistakes in the design of a program, such as the use of an inappropriate mathematical formula or control structure, recognised by incorrect results or unexpected displays. It is unlikely to generate an error message because the error is in the program design.

  Figure C6.1 Examples of trace tables

  Run including: run-time is putting a program or information system into action so that it can perform the data processing it was designed to do.

  Run-time is the time during which a program or information system is in operation. Often data has to be provided during run-time and some effects, such as run-time errors , can only be detected when the system is operating.

  Breakpoint

  is a position within the program where the program is halted as an aid to debugging. While the program is halted, the programmer can investigate the values of variables, memory locations and registers. This provides additional information to help locate errors, particularly run-time errors.

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  Routledge Library Editions: Artificial Intelligence

  • Various(Author)
  • 2021(Publication Date)
  • Routledge

    (Publisher)

  Recommendations for improving novices' computing environments are made, based upon the principle of pre-emptive design. This principle argues that users can profit from an environment in which it is not possible to make Syntax Errors, and that such an environment need neither be unduly restrictive nor overly demanding of computational resources. 1. INTRODUCTION The study of errors in computer programming has shifted in the last two decades from an emphasis on syntactic errors (e.g. Boies & Gould, 1974) to an emphasis on semantic and conceptual errors, particularly for novice programmers (e.g. Soloway, Bonar, & Ehrlich, 1983). Syntax Errors represent trivial rule violations which either cause code not to be execut- 111 112 EISENSTADT AND LEWIS Primitive Example Comments NOTE NOTE FIDO ---EATS--->MEAT {adds new triple to the data base} FORGET FORGET FIDO---HAS--->FLEAS {deletes triple from the data base} TO INSULT !XI {create new procedure called 'insult'} I 0 CHECK /XI--- VOTES---> ?Y {conditional pattern-match} lOA If present: PRINT "ONLY FOOLS VOTE" *Y; EXIT {i.e. return} lOB If absent : CONTINUE {i.e. perform next main step) 20 CHECK !XI---DRINKS--->?D 20A If present: PRINT "YUK. .. " *D "IS CRUMMY"; EXIT 20B If absent: CONTINUE 30 PRINT /XI "IS NUTS" DONE FIG. 5.1. Some SOLO examples. able at all or, in their more sinister manifestations, cause executable code to produce hard-to-detect erroneous results 1 • Semantic and conceptual errors can be characterized by the presence of ill-formed plans in a programmer's emerging repertoire of skills. The relative importance of different types of error is very hard to assess, particularly across different languages, programmer skill levels, and types of programming environment (e.g. batch vs. interactive, presence or absence of dynamic trace facilities, etc.). The seminal work of Boies and Gould (1974) argued that "syntactic errors do not appear to be a significant bottle-neck in programming".

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  eBook - ePub

  Instant Approach to Software Testing

  Principles, Applications, Techniques, and Practices

  • Dr Anand Nayyar, Anand Nayyar(Authors)
  • 2019(Publication Date)
  • BPB Publications

    (Publisher)

  16 ]. Introduction of errors in a software program is subject to human mistakes and can be classified as follows:

  • Logical error: Missing or inadequate or unclear interpretation in the source code.
  • Message error: Compiler error messages for the source code that are misinterpreted.
  • Navigation error: Moving from one function to another function is not correctly coded.
  • System error: Memory leak, hardware, and operating system related errors.
  • Incorrect requirements: Incorrect or wrong requirements.
  • Performance error: Anything related to the performance leads to performance error.
  • Data error: Incorrect data update in the database due to wrong data types used.
  • Database error: Improper normalization of database schema/design.
  • Standards: Standards not followed like improper exception handling, improper coding/design standards.
  • Incorrect design: Wrong or incorrect design.
  • Typographical error: Grammatical/lexical mistake in documents/source code.
  • Comments: Comments in the source code are not properly mentioned.
  • Variable declaration error: Wrong declaration/usage of variables in the source code, mismatch in data types of variables.
  • Boundary value analysis error: Boundary conditions are not coded properly.
  • Complexity error:

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  JavaScript for Web Warriors

  • Patrick Carey, Sasha Vodnik, Patrick Carey(Authors)
  • 2021(Publication Date)
  • Cengage Learning EMEA

    (Publisher)

  All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. CHAPTER 4 DEBUGGING AND ERROR HANDLING 118 Any error in a program that causes it to function incorrectly, whether because of incorrect syntax or flaws in logic, is called a bug. The term debugging refers to the act of tracing and resolving errors in a program. Grace Murray Hopper, a mathematician who was instrumental in developing the Common Business-Oriented Language (COBOL) program- ming language, is said to have first coined the term. A moth short-circuited a primitive computer that Hopper was using. Removing the moth “debugged” the system and resolved the problem. Today, the term “bug” refers to any sort of problem in the design and operation of a program. There are three general types of errors within a program: load- time errors, runtime errors, and logic errors. Do not confuse bugs with computer viruses or worms. Bugs are problems within a program that occur because of Syntax Errors, design flaws, or runtime errors. Viruses and worms are self-contained programs designed to infect a computer system and cause damage, compromise security, and/or steal information. Note Figure 4-1 Load-time error viewed in the Chrome browser console Error is highlighted in the document Location of load-time error Error message Load-Time Errors A load-time error , also known as a syntax error , occurs when the program is initially loaded by the browser. One of the tasks of a JavaScript interpreter is to confirm that there are no errors in the syntax.

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