Learning to code requires a balance of determination and patience. Even the most detailed and methodical of beginner coders will find that programming languages — like any language — have many rules that must be followed. The only way to get better is to practice and recognize these errors when they happen.
Some of the most common errors that beginning programmers will experience are syntax errors. A syntax error occurs when a programmer writes an incorrect line of code. Most syntax errors involve missing punctuation or a misspelled name. If there is a syntax error in a compiled or interpreted programming language, then the code won’t work.
Recognizing and understanding common syntax errors can lead to more efficient and more confident coding.
Common Syntax Errors
Programming languages carry some differences in rules and punctuation, so some syntax errors may appear more frequently than others. However, whether you’re coding in Java or Python, syntax errors need to be corrected for the program to run correctly. Here are some of the most frequent syntax errors that beginning coders may write, as well as some tips on how to fix them.
Syntax Error: Missing/Unmatched Parentheses
Parentheses are an important form of punctuation for many programming languages. It helps organize code, execute strings, and perform functions. Sometimes when a beginner is writing code, it is easy for them to forget how many parentheses have been used or if they are matched up correctly.
If one end of the parentheses is missing in the code, then it won’t be compiled. Furthermore, if the parentheses aren’t matched up correctly, then the code may perform the function incorrectly.
How to Fix It: If a syntax error appears, check to make sure that the parentheses are matched up correctly. If one end is missing or lined up incorrectly, then type in the correction and check to make sure that the code can be compiled.
Keeping the code as organized as possible also helps. If the parentheses are lined up or easy to spot, then a coder can keep track of them much more easily and not run into errors.
Syntax Error: Undeclared/Misspelled Variables
Variables hold the value of numbers, text, or data. Variables provide flexibility in coding and make it possible for coders to use programming languages efficiently. For a variable to work in code, it needs to be declared early on in the code. Inexperienced coders may accidentally forget to declare a variable or misspell it somewhere in the code.
How to Fix It: Make sure that the variable was declared in the code. If the variable wasn’t declared, then type in a line of code that declares the variable before it is used.
If you’re 100% confident that you did declare it, then check to review the code for any spelling errors or changes. If something was misspelled or changed, then the code won’t work correctly.
Syntax Error: Unmatched/Missing Quotes
Quotations are used in strings to display a statement. Either double quotes (“) or single quotes (‘) can be used inside of parentheses to display the statement, but they can’t be used interchangeably. Some coders may forget to include an end of a quote or use mismatched quotes, which will produce an error.
How to Fix It: Check to see if there is a quote missing. Match up the quotes, similarly to how you would check the parentheses. If the quotes are mismatched, then correct the error and check to make sure the code can run.
Syntax Error: Incomplete/Misspelled Return Statements
Return statements tell a program to return to a previous action. There may be a return statement or return value in the code that will be included in the code. Sometimes a return statement will have one of the previous errors mentioned — undeclared variable, missing parentheses, misspelling.
How to Fix it: Review the return statement for spelling errors or missing punctuation errors.
Syntax Error: Missing Semicolon
Semicolons are important for several programming languages because they indicate a pause in a line of code. Semi-colons are primarily used in C and Java. Coders using these languages may run into this syntax error more frequently. When a semicolon is missing in a line of code then the statement continues until the next semicolon. Usually, if there’s another punctuation or statement, it will show up as an error.
How to Fix it: Check statement ends to see if there is a missing semicolon. When you’re writing a code, get into the habit of adding a semi-colon in the same way that you would add a period at the end of a sentence.
Why is it Important to Fix Syntax Errors?
Even if a syntax error is minor, the code will not be compiled. Therefore, the coder won’t know if their program is working, so fixing syntax errors quickly is a must.
Syntax errors can be pesky, but these errors are easy to fix. As a coder gains more experience, they are less likely to run into syntax errors and gain more confidence in their coding abilities. Furthermore, learning to code efficiently can lead to many possibilities, which is why WOZ developed our software developer curriculum to prepare you for day one of your development career.
Sophia Acevedo is a journalist based in Southern California. She is a 2020 graduate from California State University, Fullerton, and a proud Daily Titan alum.