for _, v := range vectors {
		var p parser
		got := p.parseNumeric([]byte(v.in))
		ok := (p.err == nil)
		if ok != v.ok {
			if v.ok {
				t.Errorf("parseNumeric(%q): got parsing failure, want success", v.in)
			} else {
				t.Errorf("parseNumeric(%q): got parsing success, want failure", v.in)
			}
		}
		if ok && got != v.want {
			t.Errorf("parseNumeric(%q): got %d, want %d", v.in, got, v.want)
		}
	}
}

func newParser(goarch string) *Parser {
	architecture, ctxt := setArch(goarch)
	return NewParser(ctxt, architecture, nil)
}

// tryParse executes parse func in panicOnError=true context.
// parse is expected to call any parsing methods that may panic.
// Returns error gathered from recover; nil if no parse errors occurred.
//
// For unexpected panics, calls t.Fatal.
func tryParse(t *testing.T, parse func()) (err error) {
	panicOnError = true

	if len(matches[2]) > 0 {
		minor = atoi(string(matches[2][1:]))
	}
	if len(matches[3]) > 0 {
		patch = atoi(string(matches[3][1:]))
	}
	if parseError != nil {
		t.Logf("error parsing swig version %q, continuing anyway: %s", string(matches[0]), parseError)
		return
	}
	t.Logf("found swig version %d.%d.%d", major, minor, patch)
	if major < 3 || (major == 3 && minor == 0 && patch < 6) {

enormous amount of work.

Cgo takes a different approach. It determines the meaning of C
identifiers not by parsing C code but by feeding carefully constructed
programs into the system C compiler and interpreting the generated
error messages, debug information, and object files. In practice,
parsing these is significantly less work and more robust than parsing
C source.

Cgo first invokes gcc -E -dM on the preamble, in order to find out

	binBits := uint(n-1) * 8
	return n >= 9 || (x >= -1<<binBits && x < 1<<binBits)
}

// parseNumeric parses the input as being encoded in either base-256 or octal.
// This function may return negative numbers.
// If parsing fails or an integer overflow occurs, err will be set.
func (p *parser) parseNumeric(b []byte) int64 {
	// Check for base-256 (binary) format first.
	// If the first bit is set, then all following bits constitute a two's

		fmt.Printf("%s\n", scanner.Text())
	}

	if err := scanner.Err(); err != nil {
		fmt.Printf("Invalid input: %s", err)
	}
	// Output:
	// 1234
	// 5678
	// Invalid input: strconv.ParseInt: parsing "1234567901234567890": value out of range
}

// Use a Scanner with a custom split function to parse a comma-separated
// list with an empty final value.
func ExampleScanner_emptyFinalToken() {

			// Instead, turn it into a new Error that will return
			// details for all the errors.
			for _, e := range list {
				fmt.Fprintln(os.Stderr, e)
			}
			os.Exit(2)
		}
		fatalf("parsing %s: %s", name, err)
	}
	return ast1
}

func sourceLine(n ast.Node) int {
	return fset.Position(n.Pos()).Line
}

// ParseGo populates f with information learned from the Go source code

		i := strings.IndexRune(name, '=')
		if i > 0 {
			name, value = name[:i], name[i+1:]
		}
		tokens := Tokenize(name)
		if len(tokens) != 1 || tokens[0].ScanToken != scanner.Ident {
			fmt.Fprintf(os.Stderr, "asm: parsing -D: %q is not a valid identifier name\n", tokens[0])
			flags.Usage()
		}
		macros[name] = &Macro{
			name:   name,
			args:   nil,
			tokens: Tokenize(value),
		}
	}
	return macros
}

		if err != nil {
			p.errorf("parsing left shift amount: %s", err)
		}
		num = int16(amount)
	} else if p.peek() == '[' {
		// parses an element: [Index]
		p.get('[')
		tok := p.get(scanner.Int)
		index, err := strconv.ParseInt(tok.String(), 10, 16)
		p.get(']')
		if err != nil {
			p.errorf("parsing element index: %s", err)
		}
		isIndex = true
		isAmount = false

	}
	h.SetModTime(ts)

	testValidHeader(&h, t)
}

func TestHeaderTooShort(t *testing.T) {
	h := FileHeader{
		Name:   "foo.txt",
		Method: Deflate,
		Extra:  []byte{zip64ExtraID}, // missing size and second half of tag, but Extra is best-effort parsing
	}
	testValidHeader(&h, t)
}