typescript-add-error-handling

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Before1function divide(a: number, b: number): number {
2    return a / b;
3}
4
5const result = divide(10, 2);
6console.log("Result:", result);
7

After1function divide(a: number, b: number): number {
2    if (b === 0) {
3        throw new Error("Division by zero");
4    }
5    return a / b;
6}
7
8try {
9    const result = divide(10, 2);
10    console.log("Result:", result);
11} catch (error) {
12    console.error("Error:", error.message);
13}
14

Before1function divide(a: number, b: number): number {
2    return a / b;
3}
4
5const result = divide(10, 2);
6console.log("Result:", result);
7

After1function divide(a: number, b: number): number {
2    if (b === 0) {
3        throw new Error("Division by zero");
4    }
5    return a / b;
6}
7
8try {
9    const result = divide(10, 2);
10    console.log("Result:", result);
11} catch (error) {
12    console.error("Error:", error.message);
13}
14

Before1function divide(a: number, b: number): number {
2    return a / b;
3}
4
5const result = divide(10, 2);
6console.log("Result:", result);
7

After1function divide(a: number, b: number): number {
2    if (b === 0) {
3        throw new Error("Division by zero");
4    }
5    return a / b;
6}
7
8try {
9    const result = divide(10, 2);
10    console.log("Result:", result);
11} catch (error) {
12    console.error("Error:", error.message);
13}
14

Before

program

function_declaration

function "function"

identifier "divide"

formal_parameters

( "("

required_parameter

identifier "a"

type_annotation

: ":"

predefined_type

number "number"

, ","

required_parameter

identifier "b"

type_annotation

: ":"

predefined_type

number "number"

) ")"

type_annotation

: ":"

predefined_type

number "number"

statement_block

{ "{"

return_statement

return "return"

binary_expression

identifier "a"

/ "/"

identifier "b"

; ";"

} "}"

lexical_declaration

const "const"

variable_declarator

identifier "result"

= "="

call_expression

identifier "divide"

arguments

( "("

number "10"

, ","

number "2"

) ")"

; ";"

expression_statement

call_expression

member_expression

identifier "console"

. "."

property_identifier "log"

arguments

( "("

string

" "\""

string_fragment "Result:"

" "\""

, ","

identifier "result"

) ")"

; ";"

After

program

function_declaration

function "function"

identifier "divide"

formal_parameters

( "("

required_parameter

identifier "a"

type_annotation

: ":"

predefined_type

number "number"

, ","

required_parameter

identifier "b"

type_annotation

: ":"

predefined_type

number "number"

) ")"

type_annotation

: ":"

predefined_type

number "number"

statement_block

{ "{"

if_statement

if "if"

parenthesized_expression

( "("

binary_expression

identifier "b"

=== "==="

number "0"

) ")"

statement_block

{ "{"

throw_statement

throw "throw"

new_expression

new "new"

identifier "Error"

arguments

( "("

string

" "\""

string_fragment "Division by zero"

" "\""

) ")"

; ";"

} "}"

return_statement

return "return"

binary_expression

identifier "a"

/ "/"

identifier "b"

; ";"

} "}"

try_statement

try "try"

statement_block

{ "{"

lexical_declaration

const "const"

variable_declarator

identifier "result"

= "="

call_expression

identifier "divide"

arguments

( "("

number "10"

, ","

number "2"

) ")"

; ";"

expression_statement

call_expression

member_expression

identifier "console"

. "."

property_identifier "log"

arguments

( "("

string

" "\""

string_fragment "Result:"

" "\""

, ","

identifier "result"

) ")"

; ";"

} "}"

catch_clause

catch "catch"

( "("

identifier "error"

) ")"

statement_block

{ "{"

expression_statement

call_expression

member_expression

identifier "console"

. "."

property_identifier "error"

arguments

( "("

string

" "\""

string_fragment "Error:"

" "\""

, ","

member_expression

identifier "error"

. "."

property_identifier "message"

) ")"

; ";"

} "}"

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