Programming Language Comparison
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Syntactically, Pascal is much more ALGOL-like than C. English keywords are retained where C uses punctuation symbols – Pascal has and, or, and mod where C uses &&, ||, and % for example. However, C is actually more ALGOL-like than Pascal regarding (simple) declarations, retaining the type-name variable-name syntax. For example, C can accept declarations at the start of any block, not just the outer block of a function.
Semicolon use
Another more subtle difference is the type of delimiter used. In Pascal semicolons separate individual statements within a compound statement and also used to terminate a statement. They are also syntactically part of the statement itself in C (transforming an expression into a statement). This difference manifests itself primarily in two situations:
• there can never be a semicolon directly before else in Pascal whereas it is mandatory in C (unless a block statement is used)
• the last statement before an end is not required to be followed by a semicolon
A superfluous semicolon can be put on the last line before end, thereby formally inserting an empty statement.
Comments
In traditional C, there are only /* block comments */. This is only supported by certain Pascal dialects like MIDletPascal.
In traditional Pascal, there are { block comments } and (* block comments *). Modern Pascal, like Object Pascal (Delphi, FPC), as well as modern C implementations allow C++ style comments // comments
Identifiers and keywords
C and Pascal differ in their interpretation of upper and lower case. C is case sensitive while Pascal is not, thus MyLabel and mylabel are distinct names in C but identical in Pascal. In both languages, identifiers consist of letters and digits, with the rule that the first character may not be a digit. In C, the
Syntactically, Pascal is much more ALGOL-like than C. English keywords are retained where C uses punctuation symbols – Pascal has and, or, and mod where C uses &&, ||, and % for example. However, C is actually more ALGOL-like than Pascal regarding (simple) declarations, retaining the type-name variable-name syntax. For example, C can accept declarations at the start of any block, not just the outer block of a function.
Semicolon use
Another more subtle difference is the type of delimiter used. In Pascal semicolons separate individual statements within a compound statement and also used to terminate a statement. They are also syntactically part of the statement itself in C (transforming an expression into a statement). This difference manifests itself primarily in two situations:
• there can never be a semicolon directly before else in Pascal whereas it is mandatory in C (unless a block statement is used)
• the last statement before an end is not required to be followed by a semicolon
A superfluous semicolon can be put on the last line before end, thereby formally inserting an empty statement.
Comments
In traditional C, there are only /* block comments */. This is only supported by certain Pascal dialects like MIDletPascal.
In traditional Pascal, there are { block comments } and (* block comments *). Modern Pascal, like Object Pascal (Delphi, FPC), as well as modern C implementations allow C++ style comments // comments
Identifiers and keywords
C and Pascal differ in their interpretation of upper and lower case. C is case sensitive while Pascal is not, thus MyLabel and mylabel are distinct names in C but identical in Pascal. In both languages, identifiers consist of letters and digits, with the rule that the first character may not be a digit. In C, the